Survive for 5:00 in Survival Mode.
Complete a level without collecting any health or energy items
Defeat 50 enemies
Defeat any level without getting hit
Complete the game once
Post a time on all level leaderboards.
Harm the final boss using each alien before delivering the final blow.
Collect all energy and health extenders
Complete the game in less than 3 hours
Collect all keycards
Unlock all alien forms by beating levels 1-10
Defeat 300 enemies