Borderlands
 

I know I'm about 5-8 years late to this party, but I've been playing Borderlands 1 & 2 for the first time lately. Finished my first playthrough of 1 over this past weekend, and just started 2. Man, these are great games! I always wanted an RPG shooter (like Mass Effect, but with more action), and little did I know it's existed all this time. I bet this game was fun co-op too. My only "complaint" is it's light on story -- at least BL1. BL2 seems a bit better in this regard, but I wish they had a stronger underlying story like Tales from the Borderlands. Hopefully they take the hint for BL3.

Borderlands is really good. I had a ton of fun playing 4p. Enjoy.