Event 31: Mario Bros. Madness
From SmashWiki, the Super Smash Bros. wiki
Mario Bros. Madness (おれたちマリオブラザーズ, We're the Mario Brothers) is the 31st match event match of the 51 event matches in Super Smash Bros. Melee, where the player must fight Mario and Luigi in a two-minute timed match. As the title says, this event is related to Super Mario Bros. for the NES.
Similar to timed matches in Versus Mode, there is no limit on stock. Instead, a player gains a point for every KO they inflict on an opponent, and lose a point every time they are KOed or self-destruct. The player with the most points at the end of the two minutes wins.