Kill 1000 centipedes

Reach 20000 points in arcade mode

Kill 10 enemies with a single shot from a railgun

Resurrect an ally in coop mode

Reach 40000 points in arcade mode

Kill 400 scorpions

Kill 15 enemies in rapid succession

Kill 800 spiders

Detonate 50 bombs with a single shot

Kill the enemy without doing damage to it

Complete all challenges in coop mode

Complete all challenges in a single player mode

Reach 2000 points without missing a single shot

Survive for 180 seconds

Reach 30000 points in arcade mode

Kill 600 fleas