Kotomon is an iPhone game developed by former Q Entertainment staff members that worked on Rez. The game itself isn’t anything like Rez—it’s a monster game where you control a character named Kotomon, catch friendly monster, and shoot them at enemies. However, there is a musical aspect to Kotomon.
Different monsters behave in different ways when you use them. Some breathe fire. Others bounce around like a pinball. Some of them blow up on impact. Each of these adds a beat to the background music, which let you add to the soundtrack depending on how you play.
Monstars Inc. launched Kotomon at a special introductory price of $3. After May 31st, the game will go for $4. You can grab it here.