I am looking for a decent multiplayer sandbox game. Sub genre(Zombie Survival, Racing, Action, etc...) isn't super important.
I just want to be able to explore and play with friends with few restrictions.
PC Only. Any pay model is fine. I am not a huge fan of voxel games with low quality graphics.
I already have:
GTA San Andreas and IV
Just Cause 2
Test Drive Unlimited 2
Infestation Survivor Stories