>>716060751 (OP)There's better games out there, but I think L4D2 might still be the best of its formula. It just nailed the perfect pacing for this kind of game: all the maps are incredibly linear but with a minor amount of room to look around, so you're almost always moving along and funneled together unless you're doing a crescendo event, and that onslaught is high energy enough to tide you over until them.
Other games, there's too much room to separate, or you're wandering around a central area without making progress, or you're getting slowed down by combat while trying to keep moving, or so on and so forth. L4D2's design is just the right amount of disposable and focused that it works well for keeping players together without even getting to the co-op mechanics, and always feels like you can just clear them one after another.
There's other co-op shooters I enjoy more, but they're never as much of a "just jump in and beat a thing" kind of game. It's hard to describe, but whatever.