Coming out of Black Ops 2, Mob of the Dead is the best CoD Zombies map and the closest to perfection that the entire Call of Duty franchise has been. Alcatraz Prison is turned into a hellscape for this map and serves as the perfect horror-filled setting for a zombie invasion.
Black Ops 3 is a lot of fun and features some great gameplay, and some of the best maps in Zombies history. Black Ops 3 has a bundle of DLCs that add new Zombies maps. Some old, some new.