Sonic Heroes is a 3D platformer. While the preceding Sonic Adventure games for the Dreamcast featured elements of action-adventure and exploration, Sonic Heroes focuses on linear platforming and action, similar to the Sonic the Hedgehog games for the Sega Genesis. The story is also simpler than those of the Sonic Adventure games. In it, series antagonist Doctor Eggman threatens to use a weapon to destroy the world and sends out legions of robots. Four groups of three characters from the franchise’s history separately team up to put a stop to Eggman’s plans. The player navigates using one of the teams, who serve as the player characters. The teams consist of Sonic the Hedgehog, Miles “Tails” Prower, and Knuckles the Echidna; Shadow the Hedgehog, Rouge the Bat, and E-123 Omega; Amy Rose, Cream the Rabbit, and Big the Cat; and Espio the Chameleon, Charmy Bee, and Vector the Crocodile, respectively. Each team has its own campaign, called a story. Each also represents a different difficulty. Amy’s team, for example, is designed for beginners, while Shadow’s is aimed at more experienced players.