Editing Fast chess (section)

=== Armageddon ===
A variant of blitz chess where a [[draw (chess)|drawn]] game is counted as a win for Black. This guarantees the game ends decisively, so it can be used as a final tiebreaker game. It was used in tournaments such as the [[Chess World Cup]] as a tiebreaker.<ref name="armageddon_worldcup">{{cite web | url=http://www.chess.com/news/world-cup-nakamura-wins-armageddon-nepomniachtchi-appeals-4173 | title=World Cup: Nakamura Wins Armageddon, Nepomniachtchi Appeal Rejected | publisher=chess.com | date=19 September 2015 | access-date=18 January 2016 | author=PeterDoggers}}</ref>

To compensate for giving Black draw odds, White has more time on the clock. Common times are six minutes for White and five minutes for Black or five minutes for White and four minutes for Black. This can also be played with a small increment.<ref name="about_armageddon">{{cite web | url=http://chess.about.com/od/chessvariants/a/Armageddon-Tiebreakers.htm | title=Armageddon Tiebreakers | publisher=about.com | access-date=18 January 2016 | archive-date=5 March 2016 | archive-url=https://web.archive.org/web/20160305132041/http://chess.about.com/od/chessvariants/a/Armageddon-Tiebreakers.htm | url-status=dead }}</ref> If there is no increment, then difficult questions arise when players must try to flag in trivial draws,<ref name=Kaufman207>Kaufman 2021, pp. 207–210</ref> which happened in the [[Women's World Chess Championship 2008]] in the match between [[Monika Soćko]] and [[Sabina-Francesca Foisor]].<ref>{{cite web|title=Drama at World Women Chess Championship round 1 tiebreaks|url=http://reports.chessdom.com/wwcc-2008/world-women-championship-live-day-3|publisher=Chessdom|date=31 August 2008|access-date=2008-08-31|archive-date=21 October 2008|archive-url=https://web.archive.org/web/20081021080208/http://reports.chessdom.com/wwcc-2008/world-women-championship-live-day-3|url-status=dead}}</ref><ref>{{cite web|title=Appeal's Committee Ruling|url=http://nalchik2008.fide.com/news/?lang=eng&a=2&id=38|date=31 August 2008|access-date=2008-09-07|publisher=Official website of the Championship|archive-date=11 July 2011|archive-url=https://web.archive.org/web/20110711002353/http://nalchik2008.fide.com/news/?lang=eng&a=2&id=38|url-status=dead}}</ref> With a small increment, the time odds need to be larger to keep the situation balanced: Norway Chess has used 10 minutes to 7 minutes.<ref name=Kaufman30>Larry Kaufman, ''Chess Board Options'' (2021), chapter 30</ref>

Some tournaments utilise a bidding system for individual players of each match to decide how little time they would be willing to play with as black. The player with the lower bid for each match receives the black pieces with draw odds. This system minimises the perceived unfairness of Armageddon time controls that are decided in advance before a tournament with colours randomly allocated.<ref>{{cite web |last1=McClain |first1=Dylan |title=New Way to Crown Winners in Games That End in Ties |url=https://www.nytimes.com/2010/05/30/nyregion/30chess.html |publisher=The New York Times | date=31 May 2010 |access-date=11 December 2022}}</ref><ref>{{cite web |author1=NM_Vanessa |title=Nepomniachtchi Wins On Demand In Epic Armageddon Clash, Advances To Grand Final |url=https://www.chess.com/news/view/2022-rapid-chess-championship-finals-day-3 |website=Chess.com |access-date=11 December 2022 |date=21 August 2022}}</ref><ref>{{cite web |title=Chess.com Global Championship 2022: All The Information |url=https://www.chess.com/article/view/chesscom-global-championship-2022 |publisher=Chess.com |access-date=11 December 2022 |date=8 November 2022}}</ref> Such an idea is reminiscent of the logical use case of [[fair cake-cutting]].

Armageddon chess does not scale well to slower time controls, as even in rapid the necessary time odds would need to be too large; in correspondence events or engine vs. engine events, it is simply unworkable. [[Larry Kaufman]], [[Kai Laskos]], and [[Stephen Pohl]] have tested using engines ([[Stockfish (chess)|Stockfish]], [[Komodo (chess)|Komodo]], and [[Houdini (chess)|Houdini]]) an alternative solution, allowing for equal times: Black has draw odds, but is not allowed to castle short. Engine tests suggest that this is fair, although it has yet to be tried in practice by human grandmasters.<ref name=Kaufman30/>