Quite fun, though it could usesome fine tuning. Having a defensive option would be nice, and maybe having the heal as just a basic ability and not an attachment might be better (although it also might make the game to easy). I think having a system that allows you to pick up fallen enemies could also be interesting (unless that's what the "grapple" does, I wasn't able to use it because I was on keyboard and mouse). Also it would be nice if the next wave didn't appear until you've finished off the previous wave. And it would be nice if your projectiles were a different colour to the enemies.
I overall enjoyed it though!