Complete the following achievements to unlock Xbox Live Gamerscore points.

Achievement	How to unlock
A Hero's Marathon ( 15 points )	Defeat 300 enemies.
A Hero's Workout ( 10 points )	Defeat 50 enemies.
Ala Carte ( 20 points )	Complete a level without collecting any health or energy items.
All Powered Up ( 20 points )	Collect all energy and health extenders.
Key Master ( 20 points )	Collect all keycards.
No Time to Waste ( 20 points )	Post a time on all level leaderboards.
Playing with a Full Deck ( 15 points )	Unlock all alien forms by beating levels 1-10.
The Fast Lane ( 20 points )	Complete the game in less than 3 hours.
The World is Safe For Now ( 10 points )	Complete the game once.
True Hero ( 25 points )	Survive for 5:00 in Survival Mode.
Unscathed ( 10 points )	Defeat any level without getting hit.
Versatility ( 15 points )	Harm the final boss using each alien before delivering the final blow.