Bronze:
Exterminator
Objective: Defeat the giant spider.
Unstoppable
Objective: Finish a zone without losing a life.
Annihilator
Objective: Kill more than 85% of the total enemies in a zone.
Small Arms Expert
Objective: Finish a zone without using grenades or nukes.
Twin Medal
Objective: Finish a zone in Co-op mode.
Speed Freak
Objective: Finish a zone in less than 15 minutes.
Tricked Out
Objective: Max out all of the vehicle power-ups.
Silver:
Sharp Shooter
Objective: Keep your accuracy higher than 70%.
Lair Slayer
Objective: Complete all underground zones without using a continue.
Peace Maker
Objective: Finish a zone killing less than 50% of the enemies.
Survivor
Objective: Finish a zone killing 60% of the units on foot.
Gold:
Assault Hero
Objective: Complete the game.
