but after he was almost about to hit the bottom bob was rescued by mermaids and was then taken to shore where the mermaids (or mermans) took care of him.
Bob realized he has latent Magneto powers, and stops the missiles in mid air with his powers before entering an internal conflict of whether he should shoot the missiles back or just detonate them in mid-air.
so he pretended to be a zombie as well to confuse the real zombies and then they started killing each other while Bob stealthily escapes from the scene.