It's a good idea and a fun game. But it has some problems:
- It's a bit difficult to know you can wall jump in the first level.
- The smashing things just teleport upwards when they hit the ground (they don't have a upwards animation).
- The first zombies can fly like ghosts, and the last one won't move.
- You can only shoot right (it's smallest problem, since there are only a few enemies).