Sonic Advance 2 is a side-scrolling platformer similar in gameplay and style to the original Sonic Advance. The player controls Sonic the Hedgehog, who can unlock three other playable characters: Cream the Rabbit and her Chao named Cheese, Tails, and Knuckles the Echidna after defeating Doctor Eggman in specific boss battles.[1] A fifth character, Amy Rose, can be unlocked after completing the game with each character. Each character has their own unique moves and abilities. Sonic can perform an "insta-shield" that protects him for a brief moment; Cream and Tails can fly; Knuckles can glide and climb; and Amy can destroy enemies using a hammer.
In the tradition of Sonic games, gameplay consists of moving quickly through levels. Levels in the game are divided into seven "zones", each consisting of two acts of normal gameplay then a boss battle, where the player fights Doctor Eggman in order to stop Eggman from taking over the world. The player collects rings as a form of health; when the player is attacked by an enemy, their rings bounce in all directions. If the player is hit by an enemy and has no rings, they lose a life. A character will also lose a life if they fall into a gap, get crushed, or exceed an act's 10-minute limit. The game ends when all lives are lost. The player can also collect seven "special rings" to access special stages, where Chaos Emeralds are found. Special stages are on a 3D plane, where the character tries to obtain a set number of rings before time runs out in order to collect a Chaos Emerald. After beating all zones and finding all seven Chaos Emeralds with Sonic, an alternate final act is unlocked.
When all of the Chaos Emeralds are collected with the other characters, a sound test feature (where the player can listen to music) and a boss time-attack feature are unlocked, along with the Tiny Chao Garden, where toys for Cheese,[ can be purchased with rings earned in-game. Various mini-games can also be played in the Tiny Chao Garden. Other game modes include a "time-attack" mode where the player tries to beat a specific act in the shortest amount of time,and a multiplayer mode, where players can race each other through unlocked acts.