Traditional RTS games Archives

Special Issue, May 2019

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Simon Dor
Université du Québec en Abitibi-Témiscamingue

Abstract: Extensive literature underlines the importance to critically examine the phenomenon of game classification. In computer games magazines of the 1980 decade, the combination of “action”, “arcade,” or “real-time” with “strategy” is quite common. Here and there, the expression “real-time strategy” is used. But real-time strategy games as we will come to know them in the 1990s are not very similar to games labelled “real-time strategy” in the 1980s: we are simply not witnessing the description of the same gameplay or experience. Micro-histories of gameplay can underline different forms of continuities and reveal new perspectives on strategy gaming.

Keywords: Game genres; real-time strategy; strategy games; 1980 decade; history of games.

Résumé en français à la fin de l’article

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To poorly paraphrase a maxim, the history of games was written by its great successes. … a discussion of real-time strategy games invariably conjures up visions of Dune 2, Command & Conquer, and Warcraft. … One can’t deny the importance of those games, but too frequently games that were equally or more interesting, innovative, and fun escaped recognition if they weren’t obvious successes.

— T. Byrl Baker on Gamespot (s.d.).

Year 1979 sees the publication of two games that are the firsts Gamespot and MobyGames databases respectively identify as having both “real-time” and “strategy” labels. These games are War of Nerves! (Magnavox, 1979) for the Magnavox Odyssey² and Galactic Empire (Software Exchange, 1979) for the TRS-80 [Image 1 and 2].

War of Nerves! is a game where two squads fight. The goal is to eliminate the opposing commander by letting one of our soldiers reach them. Commanders are directly controlled by players’ joysticks and soldiers automatically shoot enemies. They are immobilized if they take a hit, until the commander touches them to make them move again. On the other hand, Galactic Empire is a sci-fi empire managament game, much like John Dalenske’s Empire (1973). The goal is to explore and conquer at least 20 planets. According to MobyGames, one diegetic year takes approximately four game minutes, and it can take up to 1000 diegetic years to win the game. The game can thus last up to 60 hours. These databases obviously don’t have the pretention to engage in a genre discussion, but it is still relevant to underline how the games they label are very different.

Extensive literature underlines the importance to critically examine the phenomenon of game classification (see, amongst others, Wolf, 2001; Apperley, 2006; Arsenault, 2009). In computer and video games magazines of the 1980 decade, the combination of “action”, “arcade,” or “real-time” with “strategy” is quite common. Here and there, the expression “real-time strategy” is used. But real-time strategy games as we will come to know them in the 1990s are not very similar to games labelled “real-time strategy” in the 1980s: we are simply not witnessing the description of the same gameplay or experience. Their classification in the same genre is problematic, to say the least.

Real-time strategy games (or RTS) of the 1990s and 2000s are nowadays most often linked to Dune II: The Building of a Dynasty (Westwood Studios, 1992) (see, for instance, Adams, 2006, p. 1; Egenfeldt-Nielsen, Smith and Tosca, 2008, p. 86). But Dave Morris and Leo Hartas say that computer strategy games “can trace their line of descent from the monumental hex-grid boardgames used to simulate grand swathes of history …” (Morris & Hartas, 2004, p. 9, emphasis mine). As important as wargames can be in the computer gaming history, and especially strategy games history, it is always necessary to look critically at how categorizations are retrospectively made to create lines of continuity between historical events. Foucault argues in L’archéologie du savoir that categorizations “are themselves discourse acts that needs to be analyzed as every others; they have complex relationships, but they are never intrinsic, natural, and universally recognized characteristics” (Foucault, 1969, p. 35, my translation). It is then necessary to look at historical gaming practices to know how these games sometimes qualified as “real-time strategy” were played. The challenge is to develop “a method that maintains an awareness of early film’s [or, here, game’s] difference from later practices, without defining it simply as a relation of divergence from a model of continuity (that, in fact, has not yet appeared)” (Gunning, 1990, p. 86). Strategy games from the early 1980s should be analyzed for what they are, not for how they “announce” the real-time strategy games of the 1990s.

As I will demonstrate, there is no intrinsic continuity between early 1980s wargames and real-time strategy games: RTS did not “emerge from” wargames. Early 1980s computer games that were later dubbed “real-time strategy” are no more “ancestors” of 1990s real-time strategy games than games that contributed to a certain multiplayer culture in computer gaming. Stating that real-time strategy games are historically tied to games with “real-time” aspects and strategy is as relevant as to state that role-playing games are tied to games where the player plays a character; it is true, but it does not clarify the historical explanation. Any historical continuity between cultural practices like gameplay forms is a retrospective construction. We have to look more closely at how games were discussed and played at the time in order to understand them from their contemporary perspective and justify any historical continuity that we trace according to this perspective. Some games that seem less important when focusing on the wargame and militaristic trend still have a legacy nowadays that is too often overlooked.

The goal of this paper is to begin this work by focusing on four small trends in early 1980s computer gaming. Firstly, I will summarize how “real-time” was introduced in wargames, exemplified amongst others by Chris Crawford’s games. The second trend is the combination of strategy with “action” or “arcade” aspects. Thirdly, I will explain how strategy games exist beyond the wargaming culture. And lastly, I will underline how a few strategy games were inscribed in a multiplayer culture, exemplified by Danielle Bunten Berry’s games. The goal will be to show that at least two gameplay paradigms (Dor, 2014) can be used to describe these games more accurately in their historical context: the prediction and the decryption paradigms.

Wargames in Real-Time

Greg Costikyan notes that computer wargames never really replaced traditional wargames. For him, a solitary pastime with unsatisfactory artificial intelligence could not replace a human versus human experience (Costikyan, 1996). However, some game designers literally used computer to supplement the wargaming experience. Chris Crawford released Tanktics (1978) with this in mind. The software only calculates encounters, while the visual aspect of the game is entirely assumed by a board, to a point where it is impossible to visualize the game without it [Image 3].

Both Chris Crawford and Danielle Bunten Berry (under her former name Dan Bunten) are recurrent columnists in the newly-founded Computer Gaming World magazine. Crawford signs the first paper of the publication, where he has a clear vision for the future of wargames. He writes:

At present, most people associate real-time play with arcade games. They therefore turn up their noses at the concept. Real-time play is both more realistic and more challenging than turn-sequence play. It directly solves the problem of simultaneous movement that has never been adequately solved with boardgames. It also provides a reasonable and realistic simulation of tactical combat. Tactical combat does indeed involve decision-making under time pressure. Wargames that do not include this element fall far short of simulating tactical combat (Crawford, 1981, p. 4).

For Crawford, it is basically for a more accurate simulation that wargames should embrace real-time. He released Eastern Front (1941) (Crawford, 1981) that same year, a single-player game where the German army fights USSR during World War II [Image 4]. The player selects units and gives orders using a joystick (Crawford, 2005, p. 717) and both the player and AI actions are deployed simultaneously (Donovan, 2010, p. 61). It is one of the first games that uses horizontal and vertical scrolling to slowly show a larger map, although Crawford was inspired by a software probably written by Ed Logg in 1980 (Crawford, 2005, p. 715). In a 1981 review of the game, Stanley Greenlaw explains what is scrolling, further corroborating the idea that it is quite new[1]. The player can take their time to play, but “every second you took to plan your move, the computer got another million cycles to refine its own move” (Crawford, quoted in Hague, 2002). As Greenlaw puts it: “Can you think of a more effective way to speed up slow players?” (Greenlaw, 1981, p. 30). While not a “real-time” game, it has two clear similarities with RTS games: speed of execution and simultaneous actions. Yet, Eastern Front (1941) is designed as a solo experience, where fast-thinking essentially ensure that the opponent is not too efficient. Bob Proctor explains that the game is very limited in terms of strategy, as a dominant strategy is easy to find and makes it hard to play for those who did not find it, but easy to play to those who found it (Proctor, 1982, p. 10)[2]. For Proctor, the experience of this solo game is not one of winning or losing, but to reach personal goals such as a specific threshold in score.

The game box of Legionnaire (Microcomputer Games, 1982) designed by Crawford could be the first conjunction of “real-time” with “wargame.” “Real-time” is also used in their ad (“This advertisement has no headline!,” 1982) [Image 5]. Legionnaire is quite similar to Eastern Front (1941) : the player uses a joystick to give orders to Roman legions [Image 6]. Up to eight orders can be “stacked” while the player can give their attention elsewhere. Robert DeWitt from InfoWorld explains how wargamers will appreciate being challenged in real-time (1983, p. 56). His description of the game is clear:

In typical play, Caesar might have five legions, each executing a stack of orders (i.e., moving simultaneously on the board), while the computerized enemy is attacking with twice as many units from various directions, sometimes out of sight (1983, p. 56).

The simultaneity of actions, speed of execution, and imperfect information of Eastern Front (1941) is still there, while adding this “real-time” aspect.

The next year, an ad for Combat Leader (Strategic Simulations Inc, 1983) integrates almost every keyword that connotes the hybridity between strategy and action: a “real-time wargame so fast you’ll call it a strategy arcade game” (“Combat Leader,” 1983, p. 19, emphasis preserved). French magazine Micro 7 states in a text box that it is a wargame “that has every advantages of a real-time game” (“Combat Leader,” 1984, p. 118, my translation). Roy Wagner sees a greater simplicity, since the player chooses simple commands with a letter and indicates a location where the command is to be issued (Wagner, 1984, p. 35).

This simplicity is also seen in one game retrospectively identified as an RTS: Stonkers (Imagine Software, 1983). Released only in Europe on the ZX Spectrum, Andrew Rollings and Ernest Adams suggest that it is the first RTS (Rollings & Adams, 2003, p. 161). This single-player game gives the player control of infantry, tanks, artillery, and supply trucks to take the enemy’s headquarters and port [Image 7]. Tony Bridge in Micro Adventurer explains the game principles as simple: “a large cursor which may be moved  (under keyboard or joystick direction) over the unit you wish to move” (1984, p. 21).

Information on each unit (health, morale, supply) is revealed when the mouse is over it. Bridge describes the principles of giving “orders” to units, saying that the player has to first click on them, and then to click on a destination. The player then can manage other tasks while the unit carries the order. Bridge sees it as an especially simple and short wargame that is an efficient introduction to more complex wargames such as Eastern Front (1941). Tony Tyler (1984, p. 30), editor of Big K magazine, also remarks a similarity with Crawford’s games. An anonymous reviewer in Crash notes family resemblances with arcade games because of its speed: “It gets to the point where you barely have any time left to think, and you’re punching keys all the while” (“Stonkers,” 1984, p. 102). Home Computing Weekly suggests that both audiences will be left unsatisfied: “Too little action for arcaders — not enough information for strategists” (D. C, 1984, p. 30). A letter in the “Playing tips” section of Crash magazine underlines that a dominant strategy let the player wins every time[3]. Nevertheless, readers from this magazine declared it was the “Best wargame” for 1984 (“Crash,” 1984, p. 100).  The label “real-time” implicitly calls for more action in strategy games; Stonkers shows that strategy games with action elements can definitely rivalize with traditional wargames in 1983. The combination of “action” and “strategy” will be recurrent throughout the decade.

Action/Arcade and Strategy

This hybridization between arcade and strategy is frequent at the beginning of the 1980s, and not necessarily only in classical wargames per se. Following their readers’ comments, Computer Gaming World underlines that one of the five most important events in 1982 in computer gaming is the introduction of “strategy/action games which combine strategy and arcade action” (“Some Reader,” 1983, p. 9). In his series on Atari, Allen Doum comments on the difficulty to classify games, amongst other strategy and arcade games:

In fact, distinctions between strategy and arcade games are getting harder as well. Real-time wargames such as Combat Leader and Legionnaire aren’t fast enough to be called action games yet, but next years crop will include some that will be hard to categorize (Doum, 1984, p. 22).

Luther Shaw also notes this in his review of BEZ-MX (Bez, 1982), labelled as a “wargame/arcade”. The game is described as a “a two player wargame in which the players try to destroy each other’s military-industrial strength while preserving their own” (Shaw, 1982, p. 34). The player can assign different tasks to their population to fuel their war machine, or hide them from enemy bombings at the cost of their workforce. Shaw suggests that the game would be more interesting for strategy gamers with a certain taste for arcade rather than the other way around (p. 35).

This hybrid arcade-strategy is seen by Shaw as a contemporary tendency well represented by Mission Escape[4] and Guns of the Fort Defiance (Avalon Hill, 1981). The latter is, under certain aspects, similar to what tower defenses are today. The game puts the player in the role of a group of artillery soldiers that defends a weak spot on a fort during the 1812 Canadian-American war [Image 8]. Their goal is to rout the enemy regiment, which slowly approach pixel-by-pixel. They have to use different artillery bombshells and choose an efficient fuse and elevation to hit their constantly moving target.

In two short sentences, Johnny L. Wilson pins how it mixes strategy and speed: “The cavalry, especially, have a tendency to be able to close range faster than my befuddled fingers can type orders. Hence, one often has to think ahead in terms of range estimation” (Wilson, 1982, p. 35). The speed of the game becomes significant to the point where longer-term thinking is necessary.

A few years later, another hybrid case is released: The Ancient Art of War (Evryware, 1984). The player must lead batallions composed of three different units—knight, archer, or barbarian— on the battlefield and take care of their supply and fatigue. A fight starts when two batallions meet, fight which can be managed more precisely by going into “zoom” mode, in a lateral perspective space [Image 9]. The player can create a custom campaign by choosing on which type of map the skirmish will take place, difficulty level, special rules, and the opponent (from Sun Tzu to Napoleon). Russell Sipe underlines in Computer Gaming World that all things being equal, knight beats barbarian, which beats archer, which beats knight (Sipe, 1985, p. 25); more than 20 years later, Ernest Adams and Andrew Rollings took this game to illustrate intransitive relationships in games (2007, pp. 364–365). The game is in “real-time” most of the time, except in one crucial moment: when a moving order is given, the time stops until the player selects a destination. It only plays in solo and there is not any way to create new units during play contrarily to modern RTS. Laurent Schwartz from Tilt explains in a wargame feature from 1986 that, in The Ancient Art of War, even if speed is interesting, “too many parameters direct combat so that your speed cannot determine the result” (Schwartz, 1986, p. 125, my translation).

“Real-time” and “real-time strategy” are used more than once in the next years. Within a list of entertainment software available for Amiga (Mitchell, 1986, p. 48), there are two 1984 games from Krentek Software: Rome and the Barbarian, labelled as a “[r]eal-time strategy game” », and Napoleon at Waterloo, a “simulation in real-time” retrospectively labelled as “real-time strategy” in the MobyGames database. An ad in Computer Gaming World announces TRODART, developed by GoWhile Software[5], a “war game” in real-time where there are simultaneous actions between two players by modem (“TRODART,” 1986, p. 43).

Yet, the expression “real-time” in strategy games does not necessarily mean what it commonly accepted nowadays, i.e., that the game time flows continuously and pressure their players. This expression is sometimes used to qualify games from the trilogy Sid Meier and Ed Bever released in 1985-1986 inspired by Meier’s earlier game NATO Commander (MicroProse, 1983). “Real-time” is used on the box of the first game of the series, Crusade in Europe (MicroProse, 1985) [Image 10]: “Non-stop action takes place in accelerated real-time”. The five scenarios of Crusade in Europe take place in 1944-45 where the player gives order to units, but it is still possible to pause the game on demand and still give commands. The diegetic time flows by units of 30 minutes. Schwartz (1986, p. 129) does not remark the real-time aspect of the game or of its successors, Decision in the Desert (MicroProse, 1985) and Conflict in Vietnam (MicroProse, 1986) [Image 11], while it was seen as a singular aspect of The Ancient Art of War in the same article. The definition of “real-time” used on the game box seems different from real-time in modern strategy games, i.e., that time is a constant pressure. In design notes he published for his submarine simulator Silent Service (MicroProse, 1985) in Computer Gaming World, Sid Meier states that the game is in “real-time” when an action is needed, but in  “accelerated real-time” in-between (Meier, 1986, p. 28). “Real-time” then refers to the time of a “real” action, while the accelerated time refers to the fact that, when nothing happens, the game accelerates the time. A “real-time” game then in the 1980s does not necessarily equivocates a fast game. The tradition with which real-time strategy gaming shares more in the early 1980s is probably to be found somewhere else; let us then go back to the beginning of the decade.

“Real-time” Strategy beyond Wargames

The December 1980 issue of Creative Computing has a section called “Compleat Computer Catalogue” where a reader can order games and computer products by mail using a “Reader Service Card” annexed to the magazine. One of the games is Computer Quarterback (1981), available for the Apple II, and is described as a “real-time strategy football game” (“Compleat Computer Catalogue,” 1980, p. 174). It is the first mention of “real-time strategy” as far as my research could go. In an official advertisement in the same issue, the publisher mentions that it is in “real-time” and that it is a “strategy football game” (p. 19). The title screen mentions the name “Dan Bunten,” the name under which Danielle Bunten Berry will also publish among others M.U.L.E. (Ozark Softscape, 1983) and Modem Wars (Ozark Softscape, 1988), largely considered today as landmarks in multiplayer gaming.

In Computer Quarterback [Image 12], an American football game “essentially strategic” (Harbonn, 1987, my translation), two players compete in front of the same computer, each with their own paddle. Before the match, each player assigns offensive and defensive strategies to numbers from 1 to up to 36 depending on the side and the game mode. Each player has a limited time to choose their strategy and can change it depending on what they see of their opponent’s player positioning, until the offensive team makes a move; then, the game automatically resolves the exchange. It is a game of imperfect information between two players: the choice of action does not appear on screen in order to hide that information even if players are sitting side by side. Other football computer games of the 1980s are similarly called “action/strategy” (Lee, 1987, p. 16).

Even though wargames seem like a strong influence for strategy gaming, Utopia (Mattel, 1981) could be an early influence for the genre, whether it is as the “first true proto-RTS game” (chobopeon, 2012) or “the first real simulation game, or ‘God Game,’ for a home console” (Melissinos & O’Rourke, 2012, p. 43) [Image 13]. Published on the Mattel Intellivision and designed by Don Daglow, one or two players must manage an island, accumulating gold and points, fighting pirates, natural disasters, and rebels sabotaging production. They can buy buildings (school, factory, hospital, etc.) by moving a squared cursor with the joystick and by clicking on one of the nine numbered buttons on the Intellivision controller, or directly control boats to accumulate gold by fishing or  to attack the opponent’s boats. The game uses a system of “timed turns”: it is in real time because the time flow is continuous, but turn-based in the sense that at a frequency of 30 to 120 seconds, at the players’ choice, a turn ends. At the end of a turn, the game stops for a few seconds to attribute points, add gold, and display the islands’ populations. The goal is to have more points than your opponent or to beat your personal score at the end of a predetermined number of turns.

Competition between two players is of course extremely common in electronic games, but games in the early 1980s rarely integrated this function by connecting two or more computers together. An ad box in Basic Computing presents the game Commbat (B. Schilling, 1981), claiming that it’s about time a combat game let two players fight against each other, provided they have an Apple, Atari, or TRS-80 computer with a “full-duplex modem (or a modem eliminator if the computers are in the same room). Your mission : Find and destroy the enemy’s base before he [sic] discovers and annhilates [sic] yours” (“The Company,” 1983, p. 49)[6]. To get the claims to extract uranium in the Deneb galaxy, each player fights the other with eight tanks, four reconnaissance drones, and mines, missiles, bombshells, etc. Typographic characters represent units [Image 14]. In his review of the game, George Stewart explains the inherent interest in Commbat: fighting a human opponent. This “tele-game,” as he dubs it, creates a different dynamic than when fighting computer opponents: “after all, what does a computer know about the thrill of victory or the agony of defeat?” (Stewart, 1981, p. 100). If Dobson states more than 30 years later that the game was not in real-time (Dobson, 2012, p. 3), the description made by Stewart clearly indicates the contrary:

Another essential game element is its interactiveness. You and your opponent can move, fire weapons, and select different tanks and decoys at any time. This makes the game infinitely more challenging than the typical, wait-your-turn war game played on a board. Suppose, for example, that while you’re typing in a command, you notice some enemy action through one of your three windows. You can cancel the command and make an immediate response to your opponent. You can even send him [sic] a message at any time (“Let’s quit for a while,” “Aha!” or some distracting thought) (Stewart, 1981, p. 102).

While some technical problems inevitably make modem play difficult—especially when a combat can extent somewhere from 30 minutes to 4 hours—, Stewart notes in conclusion that he sees two fundamental elements of this game that prefigures the future of computer gaming: 1) the diversity of play in human-versus-human interaction; 2) the combination of strategy, tactics, and reflexes. This combination bears family resemblances with RTS; this assemblage of gameplay elements will be part of a lot of subsequent games.

It is in the tradition of Commbat, BEZ-MX, and, of course, Computer Quarterback that the next game from Bunten Berry can be inscribed. Cytron Masters (Strategic Simulations, Inc., 1982) is “one of a new breed of games combining the action and graphics of arcade-type games with the authenticity of simulations” (Botner, 1982, p. 30), as one of its play tester puts it. Cytron Masters is the first Bunten Berry game that vaguely uses a military theme and, according to her, the first that combines action and strategy with more or less success (Bunten Berry, s.d.). Two players will fight using five unit types, each with their particularities, including commanders that can relay orders to adjacent units [Image 15].

The goal is to destroy the enemy’s command center. To create new units, the player must control some of the eight power centers, which are in a fixed number on the battlefield. By looking beyond traditional wargames in “real-time,” we can see that a tradition of multiplayer slowly emerged in the early 1980s. The roots of this multiplayer culture is still to be unveiled.

A Multiplayer Culture

Online services such as CompuServe were not available for every gamer, but some games playable through these services were not far from contemporary multiplayer games. Suzan D. Prince from the Video Games magazine identifies explicitly the game Megawars II, for CompuServe, as a “multiplayer real-time strategy”:

This high-speed, multiplayer real-time strategy game with the arcade flavor and souped-up 3-D color graphics accommodates up to 10 players at any time, with each player’s computer screen serving as his or her cockpit window through which he looks at the others (Prince, 1983, p. 24).

What Prince dubs as “timeshare games,” with persistent universes in which players log in, “… provide human interaction that is missing from player vs. system games » (Prince, 1983, p. 24). Patricia Fitzgibbons calls MegaWars as well as Empire on PLATO as “fastpaced, exciting, multi-player games of warfare and conquest” (Fitzgibbons, 1985, p. 52). Empire and MegaWars both seem to have different versions over the 1970s and 1980s, and their “real-time” aspect is difficult to evaluate.

However, one of the most renown multiplayer game from the 1980 decade is M.U.L.E. (Ozark Softscape, 1983), designed by Danielle Bunten Berry within her new company. Electronic Arts wanted to publish a previous Bunten Berry game, Cartels & Cutthroat$ (Bunten & Bunten, 1981)but SSI still had its rights. Bunten Berry then suggested to remake the game, but better, while also borrowing ideas from her own Wheeler Dealers, a “real-time stock market simulation” (Moriarty, 1998) for Apple II with an extension that can support up to four players (Moroagh, 2008). The result was M.U.L.E. (Bunten Berry, s.d.).

M.U.L.E. is a four-player “trading game” (Wade, 1985, p. 24) and a “competitive strategy title” (“M.U.L.E.,” 2001) for Atari 800, offering “an exquisite play balance of teamwork and rivalry, bitter cooperation and delicious treachery” (Moriarty, 1998). The Commodore User describes it as “[a]nother cerebral game of the management/strategy persuasion” (L. S, 1985, p. 29) and John J. Anderson underlines its educative aspect, stating that its competition necessitates cooperation (Anderson, 1983, p. 114). M.U.L.E. players develop a colony by claiming land, buying “multiple use labor elements” [M.U.L.E.] to collect resources on a planet called Irata [Image 16].

Each player takes decisions during their development phase, which has a time limit; executing all their actions faster during a phase gives a bonus in cash (Curtis, 1983, p. 12). When every player has finished their development phase, everyone can put their resources in an auction for the other players to buy them. The auction works with joysticks; buyers and sellers set their price with a gauge controlled analogically by the joystick, and a transaction occurs when an offer meets its demand. At the end of each turn, players have a score based on the value of their products and the colony in general is also evaluated. Different difficulty levels change game rules, the most difficult implying for example collusion rules where only some players can exchange goods. Micro 7 calls in the “new standard in terms of economic simulation” (Giudicelli, 1984, p. 115). The AI is perceived as very predictable, which makes playing with less than four players less attractive (Curtis, 1983, p. 13). In a similar way, Carl M. Evans (1984, p. 34) from Computer Gaming World recommends some strategies that he judges efficient against the computer, but uniquely “adequate” against humans. The game is designed as a multiplayer game and its “real-time” aspect is only meaningful in the relationship between different human players. While a lot of complex strategy games share a military setting and a complexity with real-time strategy from the 1990s, M.U.L.E. clearly show how multiplayer games have a history of their own in strategy gaming.

I have argued elsewhere that real-time strategy gaming in the 1990s could be divided in two different gameplay paradigms (Dor, 2014) and these paradigms can also be seen in the corpus I have used here. The prediction paradigm is what drive games like Computer Quarterback or M.U.L.E.; the game is based on the idea that multiple players can foresee their opponents’ possible actions and choose their action consequently. For example, in Computer Quarterback, a player knows which strategies are possible for their opponent and which ones would be more valuable for them; choosing a good opposing strategy is based on this prediction. The decryption paradigm is on the other hand exemplified by the traditional single-player wargames, from Eastern Front (1941) to Stonkers and The Ancient Art of War. The player thinks their opponent as a “puzzle” that needs to be solved. The human player is a privileged agent in the system, in the sense that everything is made up so that the experience can be interesting for them. The interest of games in this paradigm is to give enough challenge to players rather than trying to balance different similar agents. Surprise enemy actions can feel like a “jack-in-a-box,” but that can be acceptable for players if they feel like they have some agency to cope with these actions. The 1980s are dominated by decryption, but the prediction paradigm slowly emerges from some multiplayer games we have introduced here. These two paradigms are a way of constructing histories in game studies rather than following pre-established continuities such as contemporary game genres or platforms.

Conclusion

In February 1987, game designer Jim Meadows published an article in Amazing Computer where he described the genesis of one of his games, Gemini-2 (Paragon Software Corporation, 1986), a multiplayer first-person shooter between two tanks. He decorticated in details the way he succeeded in coding the interaction by modem between two computers, explaning that the first one he did for modem play in 1985—Gemini-1—was “basically a real-time strategy game that used only character graphics for the display” (Meadows, 1987, p. 19). It is impossible to attest the appearance or gameplay of Gemini-1 to see what Meadows could have meant by “real-time strategy game,” but arguably, this description seemed sufficient for him to think that his typical readership could understand what he meant[7]. The expression appeared sufficiently simple to be understood. This anecdotical evidence amongst other similar cases shows how gameplay and gaming lexicon needs to be clarified and contextualized historically.

Clearly, “real-time strategy” as an expression existed as early as 1981. But the expression does not refer to a homogeneous gameplay, design stance, or gaming practice; it can qualify a two-player football game, a solo wargame, or a strategy game with a persistent universe. These practices could have their own legitimate histories contextualizing them rather than being used as merely precursors of a future videogame genre. Taking into account different traditions shows things from different perspectives; games without a militaristic setting, for example, can be put forth for their gameplay experience rather than being only marginally considered.

If some games from the early 1980s are clearly inspired by traditional wargames, computer games quickly introduced their own “arcade” or “action” aspects and a lot of them were far from complex wargames except for their militaristic setting. “Real-time” and arcade games were a trend by themselves, eventually leading to a certain multiplayer culture that would need more research in order to grasp its importance on computer gaming culture. A history of gameplay shows us how strategy games and wargames from the 1980s do not form a “natural” continuity: gaming preferences, habits, or styles of play have a history of their own with interesting points of intersections.

This research is strongly inscribed in an historical perspective I tend to call “history of gameplay,” although it is not a new or personal perspective on the history of games. Rather than analyzing the objects themselves, I think historians should try to take into account as far as possible the way games were played, using first-hand sources when possible such as game reviews and strategy guides (Montembeault & Dor, 2018). The expression “history of gameplay” has already been used by Mia Consalvo in a similar way that I use it here (2007, p. 2). Henry Lowood used in 2004 the expression “history of interactivity” and described the idea like this: “Computer games provide the opportunity to think carefully about how to construct a history of interactivity. As we preserve interactive media, we must not lose sight of how we will document interactivity itself, which means capturing traces of activity, that is, gameplay” (Lowood, 2004, p. 6). The micro-history I have written here is part of a larger history of strategy gameplay that needs to be done.

References

ADAMS, D. (2006). The State of the RTS. IGN, April 7. Retrieved from <http://ca.ign.com/articles/2006/04/08/the-state-of-the-rts>.

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Simon Dor, Ph.D, is an Assistant Professor in videogames studies at Université du Québec en Abitibi-Témiscamingue (UQAT). His research mainly focuses on strategy games, whether it is from a gameplay or representational point-of-view, with a competitive or narrative lens, or using a cognitive, philosophical or historical approach. His teaching and research also led him to work on e-sports, immersion, ethics, and game design.

Résumé : De nombreux auteurs soulignent l’importance d’avoir un regard critique sur la classification des jeux. Dans les magazines de jeux vidéo de la décennie 1980, la combinaison des expressions « action », « arcade » ou « temps réel » avec le mot « stratégie » est fréquente. Mais les jeux de stratégie en temps réel de la décennie 1990 ne sont pas très similaires aux jeux de stratégie en temps réel des années 1980 : ce n’est pas la même jouabilité qui est décrite. Des micro-histoires de la jouabilité peuvent révéler de nouvelles perspectives sur les jeux de stratégie.

Mots-clés: Genres ludiques; jeu de stratégie en temps réel; jeu de stratégie; décennie 1980; histoire des jeux vidéo.

[1] “The player uses a joystick to move the cursor in any of the four cardinal directions. As the cursor reaches the edge of the current map the entire map will scroll in the direction of the cursor move until the cursor is stopped or the edge of the whole map is reached” (Greenlaw, 1981, p. 30).

[2] A letter from a reader corroborates this idea: “To some, Chris Crawford’s EASTERN FRONT is an impossible struggle against overwhelming odds. To others, the challenge lies not in winning, but rather whether or not ALL Russian units can be eliminated before time runs out” (Richard Thuriot, in “Strategy Game Tips,” 1984, p. 36).

[3] This dominant strategy is described by S. Hennessy: “simply move your men and some tanks to the bridge head and wait, keeping them supplied and moving everything else to your port HQ. When the enemy reach you they are so depleted of power that you come out of the battle well on top. The remaining energy will go to the occupied base (usually only a few units left) where they are easy prey for your men” (quoted in “Playing tips,” 1984, p. 77). D. Hobson adds that the most efficient method is simply to wait for every enemy unit up to the last one comes engaging yours (“Playing Tips,” 1984, p. 143).

[4] It is not clear as to which game Shaw refers to. It could be Mission: Escape! (MicroSparc, 1982).

[5] The only other mention of the game that I found, except reprint of this same ad, is on the reviewer M. Evan Brooks’ (2002) personal website.

[6] Robert A. Schilling wrote a letter in the BYTE magazine specifying that he wanted to make this game a trilogy, and that the second title was finished in April 1982 (R. A. Schilling, 1982, p. 22). My research could not identify this second game, which could have been ultimately published by another name.

[7] While Gemini-2 exists in MobyGames and on My Abandonware, I found no other trace of Gemini-1. One could assume that its distribution was very small since its creator describes it as essentially a demonstration (Meadows, 1987, p. 19).

Abstract

Bots for real-time strategy (RTS) games may be very challenging to implement. A bot controls a number of units that will have to navigate in a partially unknown environment, while at the same time avoid each other, search for enemies, and coordinate attacks to fight them down. Potential fields are a technique originating from the area of robotics where it is used in controlling the navigation of robots in dynamic environments. Although attempts have been made to transfer the technology to the gaming sector, assumed problems with efficiency and high costs for implementation have made the industry reluctant to adopt it. We present a multiagent potential field-based bot architecture that is evaluated in two different real-time strategy game settings and compare them, both in terms of performance, and in terms of softer attributes such as configurability with other state-of-the-art solutions. We show that the solution is a highly configurable bot that can match the performance standards of traditional RTS bots. Furthermore, we show that our approach deals with Fog of War (imperfect information about the opponent units) surprisingly well. We also show that a multiagent potential field-based bot is highly competitive in a resource gathering scenario.

1. Introduction

A real-time strategy (RTS) game is a game in which the players use resource gathering, base building, technological development and unit control in order to defeat its opponent(s), typically in some kind of war setting. The RTS game is not turn-based in contrast to board games such as Risk and Diplomacy. Instead, all decisions by all players have to be made in real time. Generally the player has a top-down perspective on the battlefield although some 3D RTS games allow different camera angles. The real-time aspect makes the RTS genre suitable for multiplayer games since it allows players to interact with the game independently of each other and does not let them wait for someone else to finish a turn.

In RTS games computer bots often “cheats,” that is, they have complete visibility (perfect information) of the whole game world. The purpose is to have as much information available as possible for the artificial intillegence (AI) to reason about tactics and strategies in a certain environment. Cheating is, according to Nareyek, “very annoying for the player if discovered” and he predicts the game AIs to get a larger share of the processing power in the future which in turn may open up for the possibility to use more sophisticated AIs [1]. The human player in most modern RTS games does not have this luxury, instead the player only has visibility of the area populated by the own units, and the rest of the game world is unknown until it gets explored. This property of incomplete information is usually referred to as Fog of War or FoW.

In 1985, Ossama Khatib introduced a new concept while he was looking for a real-time obstacle avoidance approach for manipulators and mobile robots. The technique which he called Artificial Potential Fields moves a manipulator in a field of forces. The position to be reached is an attractive pole for the end effector (e.g., a robot) and obstacles are repulsive surfaces for the manipulator parts [2]. Later on Arkin [3] updated the knowledge by creating another technique using superposition of spatial vector fields in order to generate behaviors in his so called motor schema concept.

Many studies concerning potential fields are related to spatial navigation and obstacle avoidance (see, e.g., [4, 5]). The technique is really helpful for the avoidance of simple obstacles even though they are numerous. Combined with an autonomous navigation approach, the result is even better, being able to surpass highly complicated obstacles [6].

Lately some other interesting applications for potential fields have been presented. The use of potential fields in architectures of multi agent systems is giving quite good results defining the way of how the agents interact. Howard et al. developed a mobile sensor network deployment using potential fields [7], and potential fields have been used in robot soccer [8, 9]. Thurau et al. [10] have developed a game bot which learns reactive behaviours (or potential fields) for actions in the first-Person Shooter game Quake II through imitation.

The article is organised as follows. First, we propose a methodology for multiagent potential field- (MAPFs-) based solution in an RTS game environment. We will show how the methodology can be used to create a bot for a resource gathering scenario (Section 4) followed by a more complex tankbattle scenario in Section 5. We will also present some preliminary results on how to deal with imperfect information, Fog of War (Section 6). The methodology has been presented in our previous papers [11, 12]. This article summarises the previous work and extends it by adding new experiments and new results. Last in this article, we have a discussion and line out some directions for future work.

2. A Methodology for Multiagent Potential Fields

When constructing a multiagent potential field-based system for controlling agents in a certain domain, there are a number of issues that we must take into consideration. It is, for example, important that each interesting object in the game world generates some type of field, and we must decide which objects can use static fields to decrease computation time.

To structure this, we identify six phases in the design of an MAPF-based solution: (1)the identification of objects;(2)the identification of the driving forces (i.e., the fields) of the game;(3)the process of assigning charges to the objects;(4)the granularity of time and space in the environment;(5)the agents of the system;(6)the architecture of the MAS.

In the first phase, we may ask us the following questions. What are the static objects of the environment? That is, what objects keep their attributes throughout the lifetime of the scenario? What are the dynamic objects of the environment? Here we may identify a number of different ways that objects may change. They may move around, if the environment has a notion of physical space. They may change their attractive (or repulsive) impact on the agents. What is the modifiability of the objects? Some objects may be consumed, created, or changed by the agents.

In the second phase, we identify the driving forces of the game at a rather abstract level, for example, to avoid obstacles, or to base the movements on what the opponent does. This leads us to a number of fields. The main reason to enable multiple fields is that it is very easy to isolate certain aspects of the computation of the potentials if we are able to filter out a certain aspect of the overall potential, for example, the repulsive forces generated by the terrain in a physical environment. We may also dynamically weight fields separately, for example, in order to decrease the importance of the navigation field when a robot stands still in a surveillance mission (and only moves its camera). We may also have strategic fields telling the agents in what direction their next goal is, or tactical fields coordinating the movements with those of the teammate agents.

The third phase includes placing the objects in the different fields. Static objects should typically be in the field of navigation. The potentials of such a field are precalculated in order to save precious run time CPU resources.

In the fourth phase, we have to decide the resolution of space and time. Resolution of space means how detailed the navigation in the game world should be. Should for example the agents be able to move to every single point in the world, or should the game world be divided into a grid with tiles of for example points in the world? Resolution of time means how often the potential fields should be updated. If the agents are able to move around in the environment, both these measures have an impact on the lookahead. The space resolution obviously, since it decides what points in space that we are able to access, and the time in that it determines how far we may get in one time frame (before it is time to make the next decision about what to do).

The fifth phase is to decide what objects to agentify and set the repertoire of those agents: what actions are we going to evaluate in the lookahead? As an example, if the agent is omnidirectional in its movements, we may not want to evaluate all possible points that the agent may move to, but rather try to filter out the most promising ones by using some heuristic, or use some representable sample.

In the sixth step, we design the architecture of the MAS. Here we take the unit agents identified in the fifth phase, give them roles, and add the supplementary agents (possibly) needed for coordination, and special missions (not covered by the unit agents themselves).

3. ORTS

Open real-time strategy (ORTS) [13] is a real-time strategy game engine developed as a tool for researchers within artificial intelligence (AI) in general and game AI in particular. ORTS uses a client-server architecture with a game server and players connected as clients. Each timeframe clients receives a data structure from the server containing the current game state. Clients can then call commands that activate and control their units. Commands can be like “move unit A to or attack opponent unit X with unit A.” The game server executes the client commands in random order.

Users can define different types of games in scripts where units, structures, and their interactions are described. All types of games from resource gathering to full real-time strategy (RTS) games are supported.

We will begin by looking at a one-player resource gathering scenario game called Collaborative Pathfinding, which was part of the 2007 and 2008 ORTS competitions [13]. In this game, the player has 20 worker units. The goal is to use the workers to mine resources from nearby mineral patches and return them to a base. A worker must be adjacent to a mineral object to mine, and to a base to return resources. As many resources as possible will be collected within 10 minutes.

This is followed by looking at the two-player games, Tankbattle, which was part of the 2007 and 2008 ORTS competitions [13] as well.

In Tankbattle, each player has 50 tanks and five bases. The goal is to destroy the bases of the opponent. Tanks are heavy units with long fire range and devastating firepower but a long cool-down period, that is, the time after an attack before the unit is ready to attack again. Bases can take a lot of damage before they are destroyed, but they have no defence mechanism of their own so it may be important to defend our own bases with tanks. The map in a tankbattle game has randomly generated terrain with passable lowland and impassable cliffs.

Both games contain a number of neutral units (sheep). These are small indestructible units moving randomly around the map. The purpose of sheep is to make pathfinding and collision detection more complex.

4. Multiagent Potential Fields in ORTS

First we will describe a bot playing the Collaborative Pathfinding game based on MAPF following the proposed methodology. Collaborative Pathfinding is a 1-player game where the player has one control center and 20 worker units. The aim is to move workers to mineral patches, mine up to 10 resources (the maximum load a worker can carry), then return to a friendly control center to drop them off.

4.1. Identifying Objects

We identify the following objects in our application: Cliffs, Sheep, Base stations, and workers.

4.2. Identifying Fields

We identified five tasks in ORTS: avoid colliding with the terrain, avoid getting stuck at other moving objects, avoid colliding with the bases, move to the bases to leave resources, and move to the mineral patches to get new resources. This leads us to three major types of potential fields: a field of navigation, a strategic field, and a tactical field.

The field of navigation is a field generated by repelling static terrain. This is because we would like the agents to avoid getting too close to objects where they may get stuck, but instead smoothly pass around them.

The strategic field is a dynamic attracting field. It makes agents go towards the mineral patches to mine, and return to the base to drop off resources.

Own workers, bases, and sheep generate small repelling fields. The purpose of these fields is the same as for obstacle avoidance; we would like our agents to avoid colliding with each other and bases as well as avoiding the sheep. This task is managed by the tactical field.

4.3. Assigning Charges

Each worker, base, sheep, and cliffs has a set of charges which generates a potential field around the object. These fields are weighted and summed together to form a total potential field that is used by our agents for navigation.

Cliffs, for example, impassable terrain, generate a repelling field for obstacle avoidance. The field is constructed by copying pregenerated matrixes of potentials into the field of navigation when a new game is started. The potential all cliffs generate in a point is calculated as the lowest potential a cliff generates in that point. The potential in a point at distance from the closest impassable terrain tile is calculated as:

Own worker units generate repelling fields for obstacle avoidance. The potential at distance from the center of another worker is calculated as

Sheep. Sheep generate a small repelling field for obstacle avoidance. The potential at distance from the center of a sheep is calculated as

Own Bases. The own bases generate two different fields depending on the current state of a worker. The base generates an attractive field if the worker needs to move to the base and drop off its resources. Once it has arrived at the base, all the resources are dropped. The potential at distance from the center of the base is calculated as

In all other states of the worker, the own base generates a repelling field for obstacle avoidance. Below is the function for calculating the potential at distance from the center of the base. Note that this is, of course, the view of the worker. The base will effect some of the workers with the attracting field while at the same time effect the rest with a repelling field. If a point is inside the quadratic area the base occupies, the potential in those points is always 10000 (potential used for impassable points):

Minerals, similar to own bases, generate attractive fields for all workers that do not carry maximum loads and a repelling field for obstacle avoidance when they do. The potential of the attractive field is the same as the attractive field around the own base in (4).

In the case when minerals generate a repelling field, the potential at distance from the center of a mineral is calculated as

4.4. The Granularity of the System

Since the application is rather simple, we use full resolution of both the map and the time frames without any problems.

4.5. The Agents

The main units of our system are the workers. They use a simple finite state machine (FSM) illustrated in Figure 1 to decide what state they are in (and thus what fields to activate). No central control or explicit coordination is needed, since the coordination is emerging through the use of the charges.

4.6. The Multiagent System Architecture

In addition to the worker agents, we have one additional agent that is the interface between the workers and the game server. It receives server information about the positions of all objects and workers which it distributes to the worker agents. They then decide what to do, and submit their proposed actions to the interface agent which in turn sends them through to the ORTS server.

4.7. Experiments, Resource Gathering

Table 1 shows the result from the Collaborative Pathfinding game in 2008 years' ORTS tournament. It shows that an MAPF-based bot can compete with A^*-based solutions in a resource gathering scenario. There are however some uncertainties in these results. Our bot has disconnected from the server (i.e., crashed) in 30 games. The reason for this is not yet clear and must be investigated in more detail. Another issue is that Uofa has used the same bot that they used in the 2007 years' tournament, and the bot had a lower score this year. The reason, according to the authors, was “probably caused by a pathfinding bug we introduced” [14]. Still we believe that with some more tuning and bug fixing our bot can probably match the best bots in this scenario.

5. MAPF in ORTS, Tankbattle

In the 2-player Tankbattle game, each player has a number of tanks and bases, and the goal is to destroy the opponent bases. In [11] we describe the implementation of an ORTS bot playing Tankbattle based on MAPF following the proposed methodology. This bot was further improved in [12] where a number of weaknesses of the original bot were addressed. We will now, just as in the case of the Collaborative pathfinding scenario, present the six steps of the used methodology. However, there are details in the implementation of several of these steps that we have improved and shown the effect of in experiments. We will therefore, to improve the flow of the presentation, not present all of them in chronologic order. Instead we start by presenting the ones that we have kept untouched through the series of experiments.

5.1. Identifying Objects

We identify the following objects in our application: Cliffs, Sheep, and own (and opponent) tanks and base stations.

5.2. Identifying Fields

We identified four tasks in ORTS: Avoid colliding with the terrain, Avoid getting stuck at other moving objects, Hunt down the enemy's forces, and Defend the bases. In the resource gathering scenario we used the two major types: field of navigation and strategic field. Here we add a new major type of potential field: the defensive field.

The field of navigation is, as in the previous example of Collaborative pathfinding, a field generated by repelling static terrain for obstacle avoidance.

The strategic field is an attracting field. It makes units go towards the opponents and place themselves on appropriate distances where they can fight the enemies.

The defensive field is a repelling field. The purpose is to make own agents retreat from enemy tanks when they are in cooldown phase. After an agent has attacked an enemy unit or base, it has a cooldown period when it cannot attack and it is therefore a good idea to stay outside enemy fire range while being in this phase. The defensive field is an improvement to deal with a weakness found in the original bot [11].

Own units, own bases, and sheep generate small repelling fields. The purpose is the same as for obstacle avoidance; we would like our agents to avoid colliding with each other or bases as well as avoiding the sheep. This is managed by the tactical field.

5.3. Assigning Charges

The upper picture in Figure 2 shows part of the map during a tankbattle game. The screenshots are from the 2D GUI available in the ORTS server. It shows our agents (light-grey circles) moving in to attack an opponent unit (white circle). The area also has some cliffs (black areas) and three sheep (small dark-grey circles). The lower picture shows the total potential field in the same area. Dark areas have low potential and light areas have high potential. The light ring around the opponent unit, located at maximum shooting distance of our tanks, is the distance from which our agents prefer to attack opponent units. The picture also shows the small repelling fields generated by our own agents and the sheep.

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(b)

Whether it’s turn-based or real-time, strategy is good for the mind.

Full control is hard to come by, but thanks to the strategy genre the power to command a million worlds is right at your fingertips. Every game’s universe abides by different rules and you better learn them fast, because we’re about to hit you with 50 of the best indie strategy games you can get your mits on! So pull up a commander’s chair or ruler’s throne, you’re about to take the controls.

50. Panzer Strategy

Panzer Strategy takes high octane battle-based warfare into the incredibly satisfying, albeit slower, realm of strategy. Develop your own unique tactics as you command your armies and weaponised vehicles through the battles of the second world war, forever altering history as you do so. The game world is based on one of intense historical accuracy. View some of the most infamous battles through the eyes of each side, developing each strategy over the course of political meetings with your country’s leaders all the way through to deployment on the battlefield.

Each unit has been developed to reflect the real life strengths and weaknesses of their equipment, so history buffs are sure to have the upper hand here. Never touched a history book in your life? That’s fine too, there’s plenty to learn about the machines that won, and lost, the second world war. What’s more, the result of each air, sea, or land battle will influence the next, and even side missions have bearing on the final historical outcome of your game. That outcome could be anything, as well, as Panzer Strategy’s non-linear narrative means every decision you make could turn the tide in battle.

49. Taste of Power

Once you get a taste of power, you’ll need a full meal to sustain you. Thankfully for medieval RTS fans, there’s far more than just a sliver of control in OneOceanLLC’s Taste of Power. The forces of Europe, China, and the Middle East have found themselves at a deadly impasse in what developers have touted as a Starcraft meets Total War alternative Middle Ages RTS.

Play as one of three factions each with their own unique skills abilities. Europeans can use gunpowder artillery and have their monks raise moral, meanwhile the Chinese have smoke grenades ready to befuddle their opponents and evade arrows. The Middle East is made up of the Timurids, warriors able to command chariots and underground tunnels beneath enemy lines alike. All the traditional mechanics of the RTS genre are in here, build your cities, manage your troops, and send forces out to conquer unknown lands; it’s not always pretty but it makes a satisfyingly complex strategy experience.

48. Achtung! Cthulhu Tactics

How do you solve a problem like the Nazis? It’s a question video games have never shied away from asking, namely because Nazis make pretty good enemies; it’s a general requirement of decent humanity to hate them and we, therefore, don’t feel so bad about shooting them in the face. Achtung! Cthulhu Tactics gives us a new reason to raise the barrel, Nazis raising tentacle monsters with science. Developer Auroch Digital took the Achtung! Cthulu tabletop hit and digitised it into a classic real-time strategy game with a sprinkling of RPG.

While Panzer Strategy gives players an all-encompassing insight into the battlefield, Achtung! Cthulu Tactics is a decidedly more focused approach to World War 2 strategy. Development is linear and on a strict trajectory; players evolve their units with a wide breadth of skills and develop their tactics according to the new threat. The narrative of Achtung! is all the better for it, with the horror of your enemies increasing with every step and a powerful sense of dread in each move. Gather your militarised team and take on the Nazis, and whatever else they’ve got brewing, in a solid RTS experience with an impressive narrative premise.

47. BANNERMEN

The lands of Valtoria have been ravaged by war, starvation, and distaster. Now it’s your turn to stand up and lay claim to the kingdom, assembling your bannermen in all regions of the map and fighting your way to victory. Pathos Interactive presents a strong, if slightly canonical, real time strategy adventure in which players inhabit a fantastical world as Lord Berrian, a commander with his eyes set on the throne. As you travel through the world you’ll have to gather resources and build communities of supporters willing to follow you into battle, micro-managing each unit’s abilities and skills while maintaining wider control over the full map.

While gameplay is pretty typical of the RTS genre, unique Temples offer some relief of the tried and tested mechanics of the RTS world. Construct Temples in key areas to unlock powerful Natural Powers, skills that can be deployed for widepread destruction. Beware, though, once you erect your Temple, your opponents will be notified and can see how close you are to being able to use your new abilities. That can be especially tricky outside of the single player campaign, if you’re playing a ranked or unranked online game, for example. Bannermen is a strategy adventure done well, with a spattering of unique mechanics to keep players interested.

46. DEFCON

Defcon takes real time strategy beyond the maths of troup count and strength on the battlefield and introduces a more psychological approach. Set during the Cold War, players are tasked with obliterating enemy territories while remaining in the safe, cozy confines of their underground bunker. While there’s certainly enough battlefield action to keep traditional battle strategy players interested, the nature of the nuclear weapons you are detonating require a new level of cunning and skill. Expose your position, or play your hand too much and you’ll have hell to pay as enemy forces are able to stamp out your efforts in one fell swoop.

You’re probably thinking ‘this sounds a lot like a game about nuclear genocide’, and you’d be right. This is an in-depth, richly populated world of nuclear war and all the alliances, paranoia, and terror that come with it. Manage your units, sure, but pay closer attention to the factions supporting you in your endeavour. Never has the phrase ‘keep your friends close and your enemies closer’ been more applicable to a virtual world.

45. Game Dev Tycoon

Ever wondered what goes on behind the scenes of your favourite games? Game Dev Tycoon not only places you in the developer’s shoes, but does it on a whirlwind tour of gaming’s biggest moments in history. As you assemble a team of crack nerds and climb the review score ladder, you’ll balance your remaining funds with the benefits of research, game engine development, contract work, and releasing the blockbuster game that will get you out of your Mum’s basement.

Use your cunning knowledge of the games industry to develop the games that sell on each console, living the high life during the casual Gameboy days all the way through to the next generation of consoles and engine technology. Learn from each success and failure to hone your craft and make a name for your studio in the world of game development. It’s easy to see why Game Dev Tycoon flourished when released in XX, giving players a chance to sit in the steering wheel of their own studio is incredibly fun. Experimenting with different combinations of genre, engine, features, consoles, topics and development specialties to produce the perfect experience to get you thinking about every title you download.

44. Mini Metro

If you’re a commuter navigating the treacherous underground world of subways and tube lines, you’ll either appreciate the complexity of our modern public transport or hate it with a deep, burning passion. Chances are it’s the latter. Mini Metro gives you the chance to put your money where your mouth is, literally saying ‘if you think it’s so bad, try making it yourself’. You start the game with three stations and it’s your job to connect them all with subway lines. Easy enough, but there aren’t only three stations in the world. Think of the congestion.

As the game continues you’ll be juggling a growing city population with new transport demands in order to accommodate the hordes of stressed commuters and tourists waiting to get from A to B. Keeping all of your trains running efficiently and ensuring a successful final design is no easy task. If you find yourself struggling in the time-sensitive main game mode, you can always kick back with some good old city planning in Creative Mode, or continue your failed design in Endless Mode which alleviates some of the passenger thresholds and train capacities. Dinosaur Polo Club’s puzzle strategy experience is definitely a unique title, just don’t spend too long critiquing the tube’s layout after becoming a transportation maestro.

43. Mushroom Wars 2

The sequel to the original Mushroom Wars RTS experience, Mushroom Wars 2 brings a refreshed art style and brand new multiplayer opportunities to Zillion Whales’ forest adventure. A single player campaign sets players on a journey across over 100 missions meanwhile online and local multiplayer with ranked league tables gives you the chance to put your fungi management to the test. Build your villages, towers, and forges all while destroying those of your opponents to seal a victory in the easy to pick up, hard to master battlefield experience. There’s plenty of charm in each hero character’s abilities and the visual design of your arena, but the mechanics are also working hard to provide a rich experience under the hood.

Defeat your enemy by taking over their buildings and obliterating their forces, all while balancing your own troops’ movement and population. You’ll have to act fast, Mushroom Wars has been designed to offer a lighter but more immediately satisfying experience with a Nintendo Switch port compared to its PC RTS counterparts, so battles rarely last more than 10 minutes a go.

42. Re-Legion

In the age of wars of ideology, Re-Legion presents a recognisable narrative overlaying a complex real time strategy experience. The leader of a cyperpunk cult, your job in Re-Legion is to convert the disillusioned masses of drug addicts and alcoholics into cult members, eventually training them up to obliterate the non-believers. This dystopian world has been raised under an oppressive cyber regime, and it’s your job as the charmingly dangerous cult leader to shape your own religion, evolve your abilities, and recruit an army of dissenters.

Lead your followers into battle and watch as they gladly lay down their lives for your cause, attacking unbelievers and corporations in order to reach enemy lines and hack their way in. Re-Legion abides by classic RTS structures, but with an intriguing story underpinning the experience’s unique atmosphere and subject matter. What happens when one narcisstic idealist utilises the power of the downtrodden? That’s up to you!

41. Satellite Reign

The worlds of Satellite Reign and Re-Legion could be one and the same. Rainy cyberpunk city streets ruled under the heavy fist of mega-corporations are often the site of riotous dissent, though Satellite Reign loses the organised linearity of Re-Legion in favour of an open world of exploration and adventure. As you move through the city you’ll come up against a range of enemy forces, it’s up to you to assemble the right team and select the best strategy for the job.

All of your work to unclench the corporate grasp over this neon-lit city is fully your own. The creative freedom afforded to players in their street-level escapades singles Satellite Reign out from other items on this list. With a game world championing emergent gameplay, players can build their armies by cloning promising members of the public and selecting from a wide talent pool of mercenary rebels, take on each moment of combat in their own unique manner, and explore a world of new objectives and missions.

Next up: Public transport woes, hordes of zombies and dinosaurs