I'm thoght about a game that uses the Jazz 2 engine about Pokemon. You're a Pokemon trainer, and instead of weapons you use different pokemon which you can select much like you select a gun in JJ2 when you hit space, you let the pokemon out to do battle with other pokemon that the trainer is helpless against fighting by himself. Instead of ammo your poemon have HP that depletes when attacked by enemies. Tokens of the pokemon can by collected by the player to recieve more health for a certain pokemon or 'capture' it if you didn't have it already. When you send out a pokemon, you control the pokemon yourself and can send it all across the level, however except in the case of a boss, you have to send the trainer to the end of the level to proceed. There also can some lvels where you have a challenge to only use such and such pokemon, or make sure the trainer doesn't get hurt once. The trainer can still be attacked by enemies even after a pokemon is sent out. Once the trainer dies you lose a life/get a gameover. If you run out of pokemon, you can recieve a low level pokemon to attack the enemies, but these low-level are typically weak. If you find the right stones, you can eveolve some pokemon and they get stronger (like a power-up) You only get so many low-level pokemon a level.