The Graphics are really amazing for a 50 MB game. You may not be as impressed if you don't take that into consideration.
The Story casts you as a robot named Blitz, who is in the improbable situation of being the only defender of a large, mostly broken, ship that's being beset by robot space pirates. Over 19 levels, you have to repair various parts of the ship in order to fire a giant cannon at the pirates.
Gameplay-wise, this is primarily a platformer, though there are a few weapons like a standard EMP pulse or upgrades like (my favorite) the homing missle filled with fireworks. The first 18 levels are divided into six areas of 3 levels each, like the electrical system or the cooling system. At the end of each area is the boss fight, and the 19th level is the Big Boss Fight. Mostly the game is on the easy side, but some of the boss fights are so difficult you'll be tempted to toss your controller at the screen. I'm thinking of one in particular that requires you to use the extremely inaccurate EMP pulse to hit the tip of a moving homing missle while dodging other homing missles… and you have to do this three times… and the third time you have to hit the same missle three times in rapid succession… Yeah, that really sucked.
The Graphics are really amazing for a 50 MB game. You may not be as impressed if you don't take that into consideration. The levels mostly look the same, but that's the nature of the setting. Some of the enemies are pretty cool-looking, and I love the fireworks homing missle as mentioned above. The Sound is mostly clangs of barrels against walls and laser whizzes, also some blips and bleeps of robot-speak. No voice acting or anything.
The Achievements are decent. The only ones that are really hard to get are Find All the Upgradium, which I can't imagine anyone having the patience to bother with unless they had a walkthrough, especially since you can get all the upgrades with barely half the Upgradium, and Spartan Blitz, which requires you to beat the game at the hardest difficulty without upgrading your 'bot at all. Of course, since some of the achievements require you to purchase all the upgrades, they're basically telling you to play through the entire game at least twice.
In Summary, at 1200 MS points ($15 USD), this is a worthy game for any platform fan, especially if you don't own a Nintendo console, since the platform selection on Xbox 360 is minimal to say the least. In fact, this might be the only 3D platformer on 360 now that I think about it. Just try to be patient with the boss fights, you'll get 'em eventually.