One of the worst games ever.
PROS
You get two games on one disc.
CONS
There are many things wrong with this game. To begin, the game is very buggy, and broken. There are numerous glitches that occur, ranging from show-stopping ones like cutscenes that won't load, or doors that won't open but should, to milder ones like enemies that spawn in midair. The worst one that occured to me was one bug where the end boss of Far Cry suddenly stopped moving, and wouldn't die. I had to kill myself and reload the previous checkpoint, and had to do the fight all over again, for about the dozenth time. The amount of bugs in the game is incredibly annoying, especially since many of them are major ones.
The story is also broken. It consists of a loosely strung-together narrative in which the protagonist is injected with some stuff that is supposed to undo human evolution and make people strong again. Or something. It doesn't really make any sense, and the plotholes and lack of explanation carry over to the expansion pack. It's poorly done, so much so that it's one of the worst stories I've ever seen in a video game.
There are also numerous problems with the controls. They are extremely imprecise, and the targeting reticule is an awkwardly large circle. What this means is that when you're shooting at someone, you don't even have to be targeted on them - you can simply have them somewhere inside the circle, and your bullets will home in on them. It's incredibly lame, and the combination of bad controls and auto-aiming that can't be turned off makes for a game where it's simply not fun to fire a gun. Not a good thing for a first person shooter.
Still with the controls, the game won't let you pause if you are either: a) doing anything, such as moving or shooting, or b) getting shot. You have to be at an absolute standstill to simply pause the game. It's amateurish programming.
The difficulty between the two games varies. The original Far Cry has a punishing difficulty. There seems to be little to no difference between easy and hard. On both settings enemies armed with pistols hslf a screen away from you will hit you with stray shots and take away a third of your damage. I'd expect something like this on hard, but on easy? Come on. The difficulty of the first game is compounded by a lack of checkpoints. It's very frustrating to clear an area after trying to get through it 10 different times, only to die from a random enemy armed with a pistol or a simple machine gun and have to do the whole thing all over again from the beginning.
Instincts, on the other hand, is ridiculously easy. After having difficulty with the main campaign, I blew through Instincts without dying until the second-to-last level, when the difficulty suddenly ramped up to come closer to the first game. It's as if the developers were criticised for making it too hard, and then went to the other extreme. Something in the middle would have been nice.
Finally, there are the graphics. While they might be okay for an XBox game, this is the 360 version we're talking about here, and the graphics simply don't cut it. Even by XBox standards the graphics aren't very good. One might argue that that's to be expected from a port; however, Half-Life 2 was also originally on XBox, and that has better graphics in the XBox version (let alone the 360 version) than the 360 version of this game does.
The achievements, likewise, are a joke. Half of them are online multiplayer - which is laughable since there is literally no one playing this online ever. As for the campaign achievements, they are as bad as Perfect Dark Zero's. Beat the campaign? Great. You get 10 gamerpoints. It's incredibly lame, which summarizes just about everything in this game.
CONCLUSION
Far Cry Instincts Predator is a game to be avoided at all costs. It is probably the worst 360 game I've ever played (well, retail game, anyway), and it is the second-worst shooter I've played (only Pariah was worse). Even fans of the genre should skip it; there are literally dozens of shooters on the 360 which are far superior. This game is simply a waste of time.