Serious Mayhem
Complete Siberian Mayhem on Serious difficulty in Singleplayer
7/9/2024
9:59:13 AM
Ultra Rare 1.0%
Massacre Party
Complete Siberian Mayhem on Serious difficulty in Cooperative with enemy multiplier set to at least x2
7/8/2024
5:24:45 PM
Ultra Rare 0.8%
Veni, Vidi, Vici
Beat the final boss in Singleplayer on Serious difficulty without loading mid-battle savegames
7/8/2024
11:13:30 AM
Ultra Rare 1.0%
Old School
Complete Siberian Mayhem without learning a single S.A.M skill in Singleplayer
7/8/2024
3:21:36 AM
Ultra Rare 1.6%
David and Goliath
Defeat Sentry Tower with sole hoverboard firepower
7/7/2024
2:39:06 PM
Ultra Rare 2.3%
Look Ma, I'm a Lumberjack!
Complete the mech sequence and kill all big enemies without shooting
7/7/2024
9:07:31 AM
Ultra Rare 1.9%