What Are Your Top 10 Local Co-op PC Games?

Anonymer

I'm looking for the best PC games that can be played in Co-op but locally--like just using 1 Desktop/Laptop and connecting 2 or more USB Gamepads. So far, I only found 1, Gauntlet.

Can you please recommend some more which are your favorites? thanks

Green613

Portal 2 ^_^

The_Waiting_Dead

Borderlands 2. Halo 1-4. and Star Wars Battlefront 2!