Here's a strategy,pick up hammer destroy his ribcage and lung which only take 1 hit but he will lose 2000 blood but he still have at least 3600 blood then start using the scalpel to cut arteliry of his heart (After you remove the mess of course) and walah.
Is it me or does it only count boss kill or something?I killed at least 500 zombies alone at rank 3 while my partner is sleeping (Just kidding) on the ground and waiting to recover and it just said I kill 2 zombies.....
Awesome game,15 minutes later,that was great,I wish they made it like they started attacking all libary in the world and attacking the main libary at the country and stuff
He kept killing me! LOL