Sonic Adventure is a 3D platform game with action and role-playing elements. Players control one of six anthropomorphic protagonists as they venture to defeat Doctor Egg and his robot army, who seeks the seven Chaos Emeralds and the entity Chaos. Six player characters are unlocked as the game progresses, each with their own story and attributes. Sonic the Hedgehog performs a spin dash, homing attack, and light-speed dash; Tails flies, swims, and attacks robots using his tails; your main man Knuckles glides, climbs walls, and punches; Amy Rose can defeat enemies using her hammer; Big the Cat is based and carries a fishing rod he can cast; and da robot can shoot laser beams.