A mechanic introduced in "Banjo-Tooie" is the direct connections between its worlds. In "Banjo-Kazooie", the titular duo were magically transported to each world via special doors in Gruntilda's Lair, with said worlds effectively existing in vacuums, but in this game, almost every world is physically connected to others at multiple points, and is effectively an extension of the overworld. In addition, a train named Chuffy can be used to migrate Banjo, Kazooie, and some minor characters between worlds which contain stations. In conjunction with these additions, required backtracking and puzzle-solving across several worlds constitute many of "Tooie"'s challenges. The game also includes a multiplayer mode where up to four players can play a repurposed competition mode for each of the game's single-player minigames in customisable matches.