This game got pretty slated on it's release last year, mostly on the fact it is just too expensive for what it is. I brought the game for £5, that is why my review is going to be much more lenient on it.
The game is a 3rd person shooter with on rail shooting sections mixed in. The enemies you fight include the iconic Terminator, and H-K, as well as new enemies made for the game (such as the main enemy type the Spider, and fast moving flying enemies called Wasps) Also the Harvester giant (featured in the film) makes a guest appearance. Each enemy type needs different tactics to take out, the Spiders for instance are impervious to damage from the front and must be flanked to attack from behind. The enemies in general are super tough with the exception of the Wasps, and for this reason there are not as many enemies as in other games of this type.