However, not all of the teams make use of all categories; the Guard and Arctic stories, for example, have no Treasure Hunt stages, due to the lack of a flying character. This game also makes use of Adventure Fields, like in the first Sonic Adventure. All of the teams (except for Knothole Team) have six characters. However, three in the Knothole Team (namely Sally, Bunnie and Chuki) must be unlocked first.