Game Achievements:

• Annihilator - Kill more than 85% of the total enemies in a zone. (10 Gamerpoints)
• Assault Hero - Complete the game. (30 Gamerpoints)
• Exterminator - Defeat the giant spider. (10 Gamerpoints)
• Lair Slayer - Complete all underground zones. (10 Gamerpoints)
• Peace Maker - Finish a zone killing less than 50% of the enemies. (20 Gamerpoints)
• Sharp Shooter - Don't waste more than 30% of your bullets. (10 Gamerpoints)
• Small Arms Expert - Finish a zone without using grenades or nukes. (20 Gamerpoints)
• Speed Freak - Finish a zone in less than 15 minutes. (20 Gamerpoints)
• Survivor - Finish a zone killing 60% of the units on foot. (20 Gamerpoints)
• Tricked Out - Max out all of the vehicle power-ups. (20 Gamerpoints)
• Twin Medal - Finish a zone in Co-op mode. (20 Gamerpoints)
• Unstoppable - Finish a zone without losing a life. (10 Gamerpoints)