So apparently you can't upgrade weapons on certain levels regardless of how high the weapon's level is. So if you click "revert all" on, say, level 3, the only thing you can put points into is the armor eater and you're with everything else being level 1. What a game-breaker! Please fix this.
I'd like to know how zombie bunnies are able to materialize through solid bullets. It would probably help me greatly in my zombie killing escapades. WE MUST HARNESS THE POWER OF THE BUNNY SO THAT WE MAY MAKE A NEW BREED OF TRUCK BUILDING SUPER SOLDIERS WITH MINIGUNS.