I have spent so much time on this game thanks to cheats, and it has given me so many hours of entertainment on an oldie.
There are 5 factions in the game. Pirates, UP (Universal Petroleum), Guerillas, Allies and China. The cool thing is about this game, is that you can be friends and enemies with anyone you want, whenever you wan't. The gun selection and choice isn't massive, but it's quite big and perfect for getting out and defeating your enemy. Also, there is a lot of missions, and you have to befriend and enemy different factions to complete these. These missions unlock airstrikes, munitions, vehicles, and other stuff I think, you can have loads of fun with all of them.
Oh I feel bad for bringing this old game back, but I think it deserves a WAY better rating, and there's a few funny bugs too. I gave it a 9 because everything in the game seemed absolutely perfect for me. The reason it didn't get a 10, was because of the easy to find bugs, but I don't think that they ruined the game for anyone.