Call of Duty: Black Ops
Call of Duty: Black Ops is the seventh game in the series and the direct sequel to Call of Duty: World at War by Treyarch. Unlike the Modern Warfare series, Black Ops isn't properly optimized for the PC and it's very CPU bound. In addition, there's also framerate issues for people who well beyond exceed the required specs.
Version Differences
Call of Duty: Black Ops uses Steamworks as its DRM, therefore, all copies of this game, regardless of purchase location, will register on your Steam account.