attrition warfare

final (match or game to decide the champion of a tournament)

battle of the brains

(collective, chiefly in compounds) many or all battles

warfare involving physical combat instead of weapons / (figuratively) activity involving large amounts of physical contact, especially sports

a contest (for a trophy, a title, etc...)

regular game, regular season

(historical) battleaxe, poleaxe

A kind of chicken fight: a Japanese game, in which one person “rides” on top of a group of supporters while wearing a hat or flag, which the person tries to defend, while their team attempts to grab the opposing team's hat or flag.

playoff; tiebreaker; a match to decide (something such as the winner)