I think a great feature for ZombieV would be to add private games for VIP players to invite players into or just play solo. I like to go into empty lobbies and get to wave 10 or 20 and just get the boss kills, but anytime I do another player just joins, kills the boss, and leaves. It's incredibly frustrating and it happens every time. This would also work as a pretty good incentive for players to buy VIP for ZombieV; I know I personally would.