Timekeeping is relevant to many types ofgames, includingvideo games,tabletop role-playing games,board games, andsports. The passage of time must be handled in a way that players find fair and easy to understand. In many games, this is done using real-time and/or turn-based timekeeping. In real-time games, time within the game passes continuously. However, in turn-based games, player turns represent a fixed duration within the game, regardless of how much time passes in the real world. Some games use combinations of real-time and turn-based timekeeping systems. Players debate the merits and flaws of these systems. There are also additional timekeeping methods, such astimelines and progress clocks.
Inreal-time games, time progresses continuously. This may occur at the same or different rates from the passage of time in the real world. For example, inTerraria, one day-night cycle of 24 hours in the game is equal to 24 minutes in the real world.[1]
In a multiplayer real-time game, players perform actions simultaneously as opposed to in sequential units or turns. In competitive games, players must consider that their opponents are working against them in real time and may act at any moment. This introduces additional challenges.
Many sports, such assoccer orbasketball, are almost entirely simultaneous in nature, retaining a limited notion of turns in specific instances, such as thefree kick in soccer and thefree throw andshot clock in basketball. In the card gamesNerts[2] andLigretto,[3] players must compete to discard their cards as quickly as possible and do not take turns.
Inturn-based games, game flow is partitioned into defined parts, calledturns, moves, or plays. Each player is allowed a period of analysis (sometimes bounded, sometimes unbounded) before committing to a game action.[4]
Turns may represent periods of time, such as hours, days, or years.[4][5] This is common in4X video games like theCivilization series[6] and world-building tabletop role-playing games. For example, inDialect, sets of turns represent eras in a society's development;[7] similarly, inThe Quiet Year, each turn represents one week leading up to a community's destruction.[8] This is also common in both video games and tabletop games withdating sim elements. For example, inPersona 5 andMonster Prom, turns represent high school class periods,[9][10] and inVisigoths vs. Mall Goths, each team's turn represents a specific hour at the mall.[11]
Turn-based games come in two main forms:simultaneous orsequential (also calledplayer-alternated).Diplomacy is an example of a simultaneous turn-based game. There are three types of player-alternated games: ranked,round-robin start, and random. The difference is the order in which players start a turn. In ranked player-alternated games, the first player is the same every time. In round-robin games, the first player selection policy is round-robin. Random player-alternated games randomly select the first player. Some games also decide the order of play using aninitiative score based on players' attributes, positions within the game, or dice rolls.Dungeons & Dragons andWizard101 are examples of this style.[12][13]
The termturn-based gaming is also used forplay-by-mail games andbrowser-based gaming websites that allow long-term gameplay of board games such asGo andchess.
Various adaptations of the real-time and turn-based systems have been implemented to address common or perceived shortcomings of these systems (though they often introduce new issues that did not exist before).[14] These include:
Timed turns are designed to prevent one player from using more time to complete turns than another. Inchess, for instance, a pair ofstop clocks may be used in order to place an upper limit on turn length.
Inexchange chess, four players on two teams play on two boards with each team taking one white and one black side. A taken piece can be given to a teammate and placed on their board. A player can abuse thisgame mechanic by taking an opponent's piece, giving it to a teammate, then waiting unusually long to play a turn on their own board—thereby allowing the teammate to use the advantage for many future moves on their board. To avoid this, players are often limited to ten seconds per move—with their opponent being allowed to remove one of the player's pawns from the board for each additional ten seconds consumed.[15][16]
Theturn-based strategy gameUtopia (1982) featured an early example of timed turns.[17] The earlyUltimarole-playing video games were strictly turn-based, but starting withUltima III: Exodus (1983), if the player waited too long to issue a command, the game would issue a "pass" command automatically, thereby allowing enemies to take their turns while theplayer character did nothing.
Time compression is a feature commonly found in real-time games such asflight simulators. It allows the player to speed up the game time by some (usually adjustable) factor. This permits the player to shorten the subjective duration of long and relatively uneventful periods of gameplay.
Many browser-basedMMORPGs allocate a number of turns that can be played within a certain period of time, called atick. A tick can be any measurement of real time. Players are allocated a certain number of turns per tick, which are refreshed at the beginning of each new tick. Tick-based games differ from other turn-based games in that ticks always occur after the same amount of time has expired.
In some real-time games, game actions are timed according to a common interval that is longer than the duration of play in the real world. For instance,non-player characters might only begin actions at the beginning or end of around. Some video games such as theBaldur's Gate series use a rounds system based on tabletop role-playing games such asDungeons & Dragons.
The "Active Time Battle" (ATB) system was introduced byHiroyuki Ito inFinal Fantasy IV (1991).[18] ATB combines menu-based combat with a continuous flow of actions and variable wait times.[19] Enemies can attack or be attacked at any time.[20] The ATB system was further developed inFinal Fantasy V (1992), which introducing a time gauge showing which character's turn is next.[21] The ATB system has since been used inVI (1994),VII (1997),VIII (1999),IX (2000), andX-2 (2003). BothFinal Fantasy XII (2006) andXIII (2009) used heavily modified versions of the system. The ATB system was also used inChrono Trigger (1995).
Insimultaneously executed games (also called "phase-based", "We-Go" or "Turn-based WeGo"), turns are separated into two distinct phases:decision andexecution. In the decision phase, each player simultaneously plans and determines their units' actions. In the execution phase, all players' chosen actions occur automatically and at the same time. One early example is the 1959 board gameDiplomacy. Video game examples includeLaser Squad Nemesis (2003), theCombat Mission series,Master of Orion series,Star Hammer: The Vanguard Prophecy (2015) andBattlestar Galactica Deadlock (2017).
Clock-based games tie all unit actions directly to the game clock. Turns begin and end depending on the duration specified for each action, resulting in a sequence of turns that is highly variable and has no set order. It is also possible for different players' actions to occur at the same time with respect to the game clock, as in real-time or simultaneously executed games. Examples of video games that use a clock-based system includeTyphoon of Steel (1988) andMechForce (1991), both originally for theAmiga.
In some games, the sequence of turns depends on theinitiative statistic of each unit, no matter which side the unit belongs to. Games of this type are still technically sequential, as only one unit can perform an action at a time, and the duration of actions is not tied to the game clock. Examples include the video gamesThe Temple of Elemental Evil (2003) andFinal Fantasy Tactics (1997).
Some games allow players to act outside of their normal turn byinterrupting an opponent's turn and executing additional actions. The number and type of actions a player may take during aninterrupt sequence is limited by the number of points remaining in the player'saction point pool carried over from the previous turn. Examples include theX-COM series of video games, the boardwargameAdvanced Squad Leader (1985), andattacks of opportunity inDungeons & Dragons. Newer editions ofDungeons & Dragons also allow aReady-action to prepare an action to be executed during the enemy's turn. This is also implemented in some video games, such asSolasta: Crown of the Magister (2020).
TheSilent Storm video game series includes an "Interrupt" statistic for each character, to determine the likelihood of out-of-turn action. In the video gameM.A.X. (1996), defensive units may be set to fire out of turn instead of on their own turn. In the board gameTide of Iron, a special card interrupts an opponent's turn to perform an action. In theMario & Luigi series, the player often has the opportunity to "counterattack" on the enemy's turn, causing damage and often halting the attack.
In some turn-based games, not all turns are alike. The board gameImperium Romanum II (1985), for instance, features a "Taxation and Mobilization" phase in every third turn (month), which does not occur in the other turns. In the video gameKing Arthur: The Role-Playing Wargame (2009), every fourth turn, the season turns to winter, the only time when buildings can be constructed. In the board gameNapoleon (1974), every third player turn is a "night turn" when combat is not allowed.
Other turn-based games feature several phases dedicated to different types of activities within each turn. In theBattle Isle series of video games, players issue movement orders for all units in one phase, and attack orders in a later phase. In the board gameAgricola (2007), turns are divided into three phases: "Upkeep", "Replenishing" and "Work." A fourth "Harvest" phase occurs every few turns.
Some games that are generally real-time use turn-based play during specific sequences. For example, therole-playing video gamesFallout (1997),Silent Storm (2003)[22] andBaldur's Gate 3 (2023) are turn-based during the combat phase and real-time throughout the remainder of the game. This speeds up portions of the game where the careful timing of actions is not crucial to player success, such as exploration.[23][24]
Other video games, such as theTotal War series,X-COM (1994) andJagged Alliance 2 (1999), combine aturn-based strategic layer withreal-time tactical combat or vice versa.[25][26]
The video gamesX-COM: Apocalypse (1997),Fallout Tactics (2001)Arcanum: Of Steamworks and Magick Obscura (2001),Pillars of Eternity II: Deadfire (2018),Pathfinder: Kingmaker (2018, added later per patch) andPathfinder: Wrath of the Righteous (2021) offer the option of turn-based or real-time mode via a configuration setting.[27][28]
In real-time games with anactive pause system (also called "pausable real-time" or "real-time with pause"), players can pause the game and issue orders. When the game is un-paused, the orders automatically execute. This offers additional tactical options, such as letting players issue orders to multiple units at the same time.[29][25]
TheBaldur's Gate series popularized pausable real-time for mouse-drivenparty-based computerrole-playing games,[30] although the mechanic was also present in earlier games such as inKnights of Xentar (1991),[31][32]Darklands (1992),[29]Tales of Phantasia (1995),[33]Total Annihilation (1997) andHomeworld (1999). InBaldur's Gate, players may also let theartificial intelligence take control during combat and press the spacebar at any time to regain control of their characters.[29] Further, inBaldur's Gate, players are able to configure the game to automatically pause when certain conditions are met, such as at the end of a round or upon the death of anon-player character. A variation of active pause, called "Smart Pause Mode" or SPM, is a feature of Apeiron'sBrigade E5: New Jagged Union (2006) and7.62: High Calibre (2007).[34][35]
Thegrand strategy games developed byParadox Interactive exclusively use pausable real-time.[25] It was the originally intended mode of theCivilization series before the developers decided to switch to turn-based.[25] It has been present in the SimCityconstruction and management simulation series sinceSimCity (1989) and is also used in theTransport Tycoon andRollerCoaster Tycoon series.
In the single-character console RPGsParasite Eve (1998) andVagrant Story (2000), the player can pause the game to take aim with a weapon.[36] InVagrant Story, this allows players to target specific body parts while the game is paused. A similar mechanic was later used in the real-time role-playing gameLast Rebellion (2010).[37]Jagged Alliance 2 (1999) andFallout (1997) allow players to target individual body parts during turn-based combat. The latter led to the creation of the V.A.T.S system in the real-time RPGFallout 3, where players could pause the game to target individual body parts.[38]Final Fantasy XII (2006) expanded on active pause combat with its "gambits" system, which allows players to collect and apply preferences to the artificial intelligence routines of partner characters, who then perform certain actions in response to certain conditions. A similar "tactics" system later appeared inDragon Age: Origins (2009)[39] andDragon Age II (2011).[40]Knights of Xentar (1991)[32] andSecret of Mana (1993)[41] also allow an adjustable artificial intelligence to take control during combat.[32][41]
Some games use atimeline as part of agame mechanic that lets players establish or alter the order of events within the game world. For example, in theindie role-playing gameMicroscope, players invent a timeline together, then select different segments of the timeline to embellish through roleplaying.[42] In the card gameChrononauts (game), everyone plays timeline cards to change the order of historical events, creating analternate history.[43]
A progress clock is a tabletop role-playinggamemaster (GM) tool for keeping track of ongoing events that cannot be handled within a single turn, such as theplayer characters' continuous headway toward defeating a challenge, the gradual approach of an enemy, or a time-limited window of opportunity. The GM draws a segmented circle to represent a clock face, then fills in a segment whenever progress develops toward the outcome. Progress clocks are important in theheist film-inspired gameBlades in the Dark and other games that adapt itsForged in the Dark system.[44][45]
Debates occur between fans of real-time and turn-based video games based on the merits and flaws of each timekeeping style.[46][47][48][49][50]
Arguments made in favor of turn-based systems include:
Arguments made in favor of real-time systems include: