a nice combo is to have, ability =Nuke; perks 1= AID; 2= long laster; 3= Margent.
So when u find a shield and have the ability, u need to stop moving and firing, your life will be heal, and zombies will be all over u without hiting u. Press "E", blow them, pick up the new power ups. Its also really usefull to reload vulcan canon.
Nice game, finished campaing. Survival have a bug. If u press "Tab" u only que paused, it gets foggy, but thats all, u can´t put the points.... i got more than 100 when y died!
 "Zombie Madness"){kind=icon}
 "Seven Deadly Sins"){kind=icon}
 "Spewer"){kind=icon}