Depends - what platform? If Playstation, I greatly enjoyed both A Way Out and It Takes Two (they're made by the same developer). Very different gameplay style

Depends - what platform? If Playstation, I greatly enjoyed both A Way Out and It Takes Two (they're made by the same developer). Very different gameplay styles, the latter being more of a platformer... but they'd get my vote for co-op games of the decade. A Way Out might be better with a platonic friend for some people, but that's up to you regarding the story in It Takes Two.