what about at wave 10 theres like a boss zombie, that only 1 person can use it untill he dies and then the next person gets it.
maybe like 800 hp and maybe a little faster than a regular zombie.
At that point the players with higher tier weapons can take out a poison zombie [400HP] out in only a couple of seconds - er, rather, a single player is capable of doing that even if he or she has the right weapon. IMO, if it is a one-player-at-a-time boss zombie, make it something harder, 1600 HP?
I also strongly urge the removal of any recoil effect from being shot - if we no longer stop in place from being shot, then we can move farther before death, which may alleviate some of the camping issues at least a little... plus, if humans don't recoil like that from being attached by a human, why should zombies when hit by a human?