Here's another incomplete app that I will not get to for a while.

I think I got the hard parts down. And since I won't get to it for a while, why don't you pick it up?
Here's what you can do next:
- Implement life gain and loss
- Implement PowerUps and scoring for PowerUps
- Implement bonus targets
- Implement warp across the map for mobs (it's already in place for avatar)
- Detect winning conditions and advance to the next round
- Rename and restyle the app
- Add more settings
There's a lot of goodness in this app to check out regardless of whether or not you continue:
- Components: there are very few objects in the tree view. That's because everything's been simplified into components!
- Besides the components for games, there's a header/footer component that is flexible in use.
- Custom properties: THERE'S LOTS OF THESE. See what I pick out.