I liked how you make the fusion character become huge. Your idea is really good, fighting off these skeleton waves was fun, specially when I got to kill all of them in super saiyan mode. My suggestion would be to make the characters more distinguishable, maybe add colored clothing. I had a hard time telling them apart from time to time. Also, check out my game, I guess our ideas were close together. In it, you control two characters too, with these keybindings.