Good Cogs Never Rust
Not unlocked yetDefeat a Winter Story level without letting one Cog disappear.
Bomberman!
Not unlocked yetBlast at least 8 Martians with one Bomb!
The butterfly effect
Not unlocked yetSuccessfully start a chain reaction using 4 or more Explosive Barrels!
The Cow is a lie
Not unlocked yetBehold a Cow going through a quantum wormhole!
GLaDOS is not gonna be glad!
Not unlocked yetWitness or cause the collapse of a quantum wormhole.
Winter is coming
Not unlocked yetSurvive fall!
Trick or Treat!
Not unlocked yetSurvive all five 'This is Halloween!' bonus levels!
Spring Break
Not unlocked yetSurvive spring!
Sunset Rider
Not unlocked yetSurvive summer!
Ain't that a cute little gun?
Not unlocked yetSurvive all five 'Meet the Martians' bonus levels!
Like a Boss!
Not unlocked yetRepel the Martian threat for good!
Challenge Accepted!
Not unlocked yetSave all the cows throughout all the Challenges.
Impeccable Fall
Not unlocked yetSave all the cows on every Story level of fall.
Smashing Pumpkins!
Not unlocked yetSave all the cows on all the 'This is Halloween!' bonus levels.
Who you gonna call?
Not unlocked yetSave all the cows on all the 'This is Halloween!' bonus levels in Veteran difficulty.
I MAID A GAM3 W1TH M4RT1ANS!!!1
Not unlocked yetSave all the cows throughout the whole 'Maid Raid' Challenge category.
Party time! Excellent!
Not unlocked yetSave all the cows throughout the whole 'Hard Rock from the Red Planet' Challenge category.
Teenage Martian Ninja Troopers
Not unlocked yetSave all the cows throughout the whole 'Ninjas in the Snow' Challenge category.
The Old School Republic
Not unlocked yetSave all the cows throughout the whole 'Back to Basics' Challenge category.
The shield is down!
Not unlocked yetSave all the cows throughout the whole 'Weird Science' Challenge category.
Flawless Spring
Not unlocked yetSave all the cows on every Story level of spring.
Save ALL the Cows!!
Not unlocked yetSave all the cows on every level of the Story mode.
Perfect Summer
Not unlocked yetSave all the cows on every Story level of summer.
For science...you monster.
Not unlocked yetSave all the cows on all the 'Meet the Martians' bonus levels.