This is a film discription from Wikipedia. I have actually seen this film and this review is pretty much accurate. It is hilarious. I couldnt find a picture of the doomtrooper but it is fuck off scary.

Set during WW2 SS Doomtrooper begins with six prisoners from either England or America, being given a secret mission, which entails them travelling to Germany in order to find out what the Nazis are working on, and then destroy it, in return for freedom. They parachute into German territory, and realise that they still have a long way to go before they reach the castle where the experiments are happening. Two of the Americans get separated from the rest of the group, and start making their way toward the meeting point for the rest of the group.
Meanwhile, Professor Ullman, the Nazi scientist, asks if he can unleash his monster on the good guys. The head guy says yes.

The two separated who will now be referred to as "Nervous Guy" and "Cool Sniper Guy" encounter the Doomtrooper. It is all blue, with glowing veins, about 10 feet tall, and has some kind of gun on its wrist. They battle it, firing their guns at it to no avail, just when things look their bleakest, the rest of the team comes. But Nervous Guy is still very nervous, so he tries to make a run for it, only to be shot and killed by the Doomtrooper. The team all throw grenades at the Doomtrooper and escape.

When the Nazis hear that the Doomtrooper has failed to kill the Allies, they send for it to be recaptured. When the Nazis arrive to capture it, it massacres them all, electrocuting one with its hands, and gunning down all the others. The rag-tag group of rebels, consisting of 'Captain Guy' the aforementioned "Cool Sniper Guy", "English Bomb Guy", "English Guy", and "American Smart-ass Guy", realize that the monster is still alive, and try to find a place to hide for the night. What they find is instead a French Resistance hideout. In there they meet 'French Chick' and 'French Guy' who tell them where the castle is. During the night, the Doomtrooper finds the French base, and kills everyone inside, except for the main characters.

Back at Castle Von Nazi, the head Nazi guy, yells at the Scientist, after learning that the Doomtrooper has killed his team. He tells the Scientist that he can't make any more monsters. The scientist then shoots him, and takes command of the base.

The good guys meanwhile, find a tank, kill the driver, who can also fire the gun without assistance, and hit the Doomtrooper with a shell. Yet again this does no damage. They then drive away from the creature, which cannot chase them because a building collapsed on it. At night they make a plan which involves them capturing a German weapons depot, and blowing the creature up inside the depot. They capture it by driving the tank in, which the Germans believe to be German, and machine gun everyone. Then they lead the Doomtrooper to the depot, lock it inside, and blow up the entire facility, "French Guy" dies during this, as he tries to hold the door shut, the Doomtrooper electrocutes him, he catches fire and disintegrates.

The good-guys then make their way to the castle, unbeknownst to the fact that the Doomtrooper survived. Along the way "Cool Sniper Guy'" gets shot in the eye, and "English Guy" gets shot as well. They make it to the castle, shoot more or less everyone, and then "English Bomb Guy" detonates a bomb he is sitting next to which kills all the Germans, in order to save the good guys. It is then revealed the "English Guy" did not die, and that the bullet was stopped by a medal of his. He is soon tracked down by the Nazis; they stand in a circle around him and empty around 20 magazines into him. When in the Nazi base, the good guys beat up the Nazis, and try to self destruct the base, while they are doing this, the Doomtrooper returns, killing everyone but the Scientist, who gets shot by "French Chick". "Smart Ass American Guy" gets his head exploded by electricity when he's trying to do something to blow up the castle.

Meanwhile 'Captain Guy' cuts the Doomtroopers hand off with his knife, and then sticks two electrical cords onto it's head. They escape as the whole castle explodes, and they also discover that "English Bomb Guy" survived. It shows them back in America, telling the American General not to try to recreate the same creature, but they suspect he will anyway. To get him back they steal a Jeep.