An impulse-based turn system is a
game mechanic
In tabletop games and video games, game mechanics are the rules or ludemes that govern and guide the player's actions, as well as the game's response to them. A rule is an instruction on how to play, a ludeme is an element of play like the L-shap ...
where a
game turn
A game is a structured form of play, usually undertaken for entertainment or fun, and sometimes used as an educational tool. Many games are also considered to be work (such as professional players of spectator sports or games) or art (such ...
is broken up into a series of discrete, repeating segments, or impulses. It can be considered a fairly complex mechanic, but has been used in three games that have enjoyed long-term success, the wargames ''
Star Fleet Battles
''Star Fleet Battles'' (SFB) is a Military tactics, tactical board wargame set in an offshoot of the ''Star Trek'' setting called the Star Fleet Universe. Originally created in 1979 by Stephen V. Cole, it has had four major editions. The current ...
'' and ''
Car Wars
''Car Wars'' is a vehicle combat simulation game developed by Steve Jackson Games. It was first published in 1980. Players control armed vehicles in a post-apocalyptic future.
Game play
In ''Car Wars'', players assume control of one or more ca ...
'', and the ''Hero System''
role-playing game
A role-playing game (sometimes spelled roleplaying game, RPG) is a game in which players assume the roles of player character, characters in a fictional Setting (narrative), setting. Players take responsibility for acting out these roles within ...
(also known as ''
Champions
A champion (from the late Latin ''campio'') is the Victory, victor in a challenge, Competition, contest or competition. There can be a territorial pyramid of championships, e.g. local, regional / provincial, state, national, continental and w ...
'' or ''
Fantasy Hero
''Fantasy Hero'' is a role-playing game book originally published by Hero Games in 1985 that allows gamemasters to plan and present fantasy role-playing games using the Hero System rules. Several revised editions of the book have subsequently bee ...
'').
It is most often seen in games that feature high-paced combat where units can move much further in one turn than common effective weapons ranges. (In ''Star Fleet Battles'', a ship may move as far as 31 hexes in a single turn, and can usually move 20. 'Effective' weapon's range is generally 4-8 hexes at best.)
Comparison between impulses, turns, and rounds
There is potential confusion over the use of the terms impulse, turn, and round in modern tabletop gaming. In games that use the term impulse, such as tabletop
wargames
''WarGames'' is a 1983 American science fiction techno-thriller film written by Lawrence Lasker and Walter F. Parkes and directed by John Badham. The film, which stars Matthew Broderick, Dabney Coleman, John Wood, and Ally Sheedy, follows Dav ...
, a single game turn generally comprises multiple impulses, in which players take some portion of their possible actions; for example, activating a subset of their units. Thus, an impulse represents one subdivision of a larger structure—the turn. However, in certain other styles of games (
Euro-style strategy games in particular), a similar two-level structure can be found, but with different terminology used by convention. In such games, each time that a player acts is described as a turn, with multiple turns potentially comprising a round.
The distinction between these conventions is partly historical and partly cultural, and most games use one convention or the other. However, as defined, a game could theoretically use a three-level structure wherein a single game round comprises multiple turns which comprise multiple impulses.
Game design
Star Fleet Universe
Board game terminology
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