Ah yes, Orion: Prelude, or as it will always be known to me, Orion: Dino Horde! This game has been quite criticized through the years (and in all honestly quite rightly so). they game if filled with bugs and lots of tedious grinding achievements. Still, despite all that I can't help but to love it. In fact it is the only game which I haven't uninstalled after reaching 100%.
So, there's no story to follow in this game and it's a pretty straightforward king of game. You're dropped as one of three classes (assault, recon and support) into a base where you're supposed to defend a generator against incoming waves of attacking dinos that don't enjoy your presence there. If all teammates dies or the generator is destroyed (a timer starts when it reaches 0% health and if it isn't repaired before time runs out it's destroyed) you all loose. If you survive all waves (10 for normal games and 30 for conquest games) then you win. Pretty simple. To your help you can buy a quite big assortment of weapons and perks and each class comes with a specific perk of their own (assault can jetpack, recon can cloak and support can heal).
This game has a lot of various pvps but there are only a couple which I really enjoy such as king of the hill and team elimination. The place where this game really shines is in regular Survival mode when you play together with a good, tight and cooperative team. This is where this game is at it's best! I don't think I've made as many friends in any game as I've made in this one.
So, in conclusion, if you want a good cooperative game and don't mind a few bugs here and there and can either ignore, or work through all the grinding achievements then yes, you will enjoy this game!