Army of Two: The One With Best Friends Forever
While most shooters tend to be built around making you an army of one, 2008’s Army of Two is all about friendship and cooperation between a pair of soldiers who really should have been romantically involved. Elliot Salem and Tyson Rios deeply need each other. Sometimes they need each other to open heavy doors, or flank enemies, or provide cover. During particularly romantic situations the pair can go back-to-back, which doesn’t really seem like it would help much in a situation where two people were surrounded by enemies with guns, but somehow it did.

Were Army of Two’s co-op play a mere suggestion, it wouldn’t be on this list. But buddy action is the core gameplay mechanic here. You have to be friends, whether with another live player or the AI, to get through the game. I think it’s kind of sweet, really.