Holy crap! This is possibly the best game ever, and no matter what you say Buster, yes it does have a plot. The prestory is about the Locust which are an alien species living beneath the surface of this planet you live on, after a while the technology of the world makes the Locust aware of you and they decide they want the planet for themselves as they attempt to spread their hive. The main character Seras something or other is one of the soldiers caught up in the first conflict where you drive them underground for a short time, but after defying an order you are courtmartialed and sent to jail. You start off in prison for a war crime (not to be uncovered until later in the game), but an old friend comes and busts you out of the decaying prison now being over run by Locust, you and your friend escape and rejoin the military which is now desperate for man power since at this point the Locust have over run the planet and Humanity is almost driven to extinction. After rejoining a new unit (delta group) you are sent to find the Alpha squad that is lost deep in enemy territory, you make your way in losing two squadmates while gaining more (best is Cole "Train" an ex-football quarterback), after saving what's left of Alpha squad your new squad is reassigned a mission that could save humanity. You must take a tracking device to the deepest point of Locust territory so that you can map out their hive and destroy them for good.
I ate dinner and then posted this.
Best game ever, the mace grenades, the chainsaw gun (lancer rifle) and the variety of characters that can add a touch of grim humor in the most terrifying scenes.
Oh and the Locust are ugly as sin. Especially their beserkers (giant blind Locust that are atleast twice the normal size and coated a naturally resiliant exoskeleton).