So i have own every cod at some point, but because i like to recycle my games via gamestop, not anymore. But i digress, after a few years of break from cod, i bought back my copy of black ops 1 cuz i remembered that the zombie mode was a blast. And it still was! (with friends of course.) The game even remembered all my expansion packs, and that includes all of them except the one where you get the shangri-la map. After a few cold ones there is no better/harder co-op zombie massacare than black ops zombies.