I am sorry but this is one of the most boring games I have ever played !
I played this game alone because games don't have to use co-op to be good( I play l4d alone and I still have a lot of fun with it despite the co-op is almost essential ) the game is an FPS with a RPG and Dungeon crawler design and you chose between 4 characters and all you do in this game is doing quest and finishing quests as if this was an MMO, and speaking of MMOs is shares the color of items with WOW like how purple is rare and called epic and green is uncommon and white is common etc, and it also takes from WOW the talent tree for each character where every time you level up you can spent a point into on of these tree to skill up a certain ability or to gain a new one.
This game's quests are beyond repetitive and you will eventually get bored, some characters are introduced in a comic book way like having a small zoom and a colorful background with the name splatting on the background but none of these characters have anything interesting to say and almost all of them are easily forgettable , and the story of this game lacks real depth which makes the boring game even more boring.
However the game is not that bad I mean the Controls feels right, the gunplay is great, good variety of weapons, the graphics are weird but still appealing to look at and the most memorable characters in this whole game are the small robots who are just plain funny and witty.