There was a game for the Genesis (maybe SNES) that was a shooter. It could be played coop, and between each level you could each pick one super weapon to take with you. You could only use each potential pick one time in the game (per player). It was too easy as a game, at least in coop mode. But I really enjoyed it, and I’d like to remember the name.
Side-scroller? Top-down? Chaos Engine, maybe?
It was vertical, and it was a spaceship style…it might have had an acronym title. But it was definitely a scrolling verticle game. I should have said SHMUP rather than shooter.