Unlike the other Kirby games, Kirby & The Amazing Mirror features a maze layout, and is traversed in a Metroidvania style. The game map branches out in several directions and, providing Kirby has the proper power at his disposal, he is able to go anywhere in almost any order, excluding the final sequence.
The player explores the worlds, solving puzzles, defeating enemies, and collecting items. Occasionally, a sub-boss will be encountered, at which point the screen will lock into place until the boss is defeated. Swallowing a sub-boss after defeat usually grants a rare or exclusive copy ability. The player will also occasionally encounter "rest areas" of sorts.
The player can collect various items to improve in-game performance, such as extra health points and lives, food to replenish health, and batteries for the Cellphone. The game also features two other collectibles: music sheets, which act as a sound test mode once the music player item is found, and spray paint, which can be used to recolor the player's Kirby. There are also three minigames accessible from the menu, which support single player and multiplayer:
Speed Eaters- A game in which the four Kirbys are seated around a covered platter. Once the lid is whisked away at a random time, the fastest person to press the A button and suck in the food on the platter is filled up more (measured by a gauge above each Kirby).
Crackity Hack- A game in which the four Kirbys are challenged to break a rock as much as they can, in a similar style to a microgame from Kirby Super Star.
Kirby's Wave Ride- A game in which the Kirbys, atop Warp Stars, race over a water track that varies in length and complexity depending on the difficulty setting, similar to the GameCube racing game Kirby Air Ride.
The game also features multiplayer, and the player can call other players or CPU-controlled Kirbys to the location with an in-game cell phone. There are several new powers in The Amazing Mirror, such as Cupid (called Angel in the Japanese version), which allows Kirby to fly around with wings and a halo and fire arrows; Missile, which turns Kirby into a missile that can be guided in any direction and will explode on contact with a wall or an enemy or when the B button is hit; and Smash, which gives Kirby the abilities he had in Super Smash Bros. Melee.