active chess by FIDE between 1987 and 1989. For the FIDE World Rapid Championship, each player has 15 minutes plus 10 seconds additional time per move starting from move 1. Blitz Time controls for each player in a game of blitz chess are, according to FIDE, 10 minutes or less per player. This can be played with or without an increment or delay per move, made possible by the adoption of digital clocks. Three minutes with a two-second increment is preferred. In the case of time increments, the total time per player for a 60-move game must be 10 minutes or less (hence averaging 10 seconds or less per move). For the FIDE World Blitz Championship, each player has 3 minutes plus 2 additional seconds per move, starting from move 1. Bullet A variant of blitz chess, bullet chess games have less than three minutes per player, based on a 40-move game; some chess servers rate one-minute-per-player games separately. Lower time controls are called "hyperbullet" and "ultrabullet" for 30-second-per-player and 15-second-per-player games, respectively. Other common time-control options for bullet games include two minutes with one-second increment, one minute with a two-second increment, or one minute with one-second increment. The term lightning can also be applied to this variant. The use of increment in bullet chess is primarily to avoid issues with latency as well as so-called "dirty flagging". Online bullet chess avoids practical problems associated with live bullet chess, particularly players accidentally knocking over the pieces. Playing online also allows premoving, or committing to a move before the opponent has taken their turn. Armageddon A variant of blitz chess where a 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 is used in tournaments such as Chess World Cup as a tiebreaker. 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. 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 lowest bid for each match receives the black pieces with draw odds. This system minimises the