Thanks for putting this together! I like the funny little pizza demons a lot, and I'm a big fan of arena battler games. I managed to make it up to Wave 4 on my second try.
The basic premise is good, but I think Pizzageist could feel significantly better if you made some key changes: reduce the map size, increase the player's attack range, and make each sibling tag in and out of the game instead of having all three on screen at the same time. It was a bit frustrating to lose lives even though I couldn't control their movements to dodge pepperoni.