Best 4-Player Co-op Game?

[Starik20X6]

LittleBigPlanet, Kirby Adventure Wii/Kirby Return to Dreamland (wherever you live), if you all have DS', Zelda: Four Swords, which is free to get at the moment. They're the first that come to mind.

 

[VladG]

Left4Dead would be my first choice. Kinda short, but amazing fun.

LotR: War in the North is only 3 player, but it's fun.

Dead Island is fun in coop too if you don't mind the stupid quests, bad level structure and idiotic AI.

Lots of games you can get on Steam for the PC, low end ones too. Magicka, Terraria, Bunch of Heroes (not local)

Also Heroes 3. Local play, god I spent hours playing that with friends...

 

[xgeua]

Halo 3/ODST/Reach
http://www.youtube.com/watch?v=F3vDtRLUA-I
http://www.youtube.com/watch?v=QjWf4TKHZaE&feature=related

 

[Yopaz]

Splosion Man is simply brilliant. One of my all time favourites also Ms. Splosion Man.
Super Smash Bros. Brawl is great too, though that's only 2.
Also the upcoming Resident Evil game probably got 4 player co-op so check that out.