Fixing bugs in my game on xcode 7 macbook air

Debugging reveals hidden monsters remained active after being shot; adding hit-state logic prevents repeat collisions and corpse reappearance. Second monster is linked to an orange dead-state block, leaving corpses; plans expand to faster monsters and successive waves. Apparent random deaths are traced to the bullet respawning at monster locations; moving it 1,000 pixels offscreen fixes the collision.

Iterative debugging shifts the project from basic shooting toward a functioning multi-wave zombie game.