Here is the full list of all 53 The Basement Collection achievements.
Get XXXX points in one playthrough in Grey Matter
Get XXX points in one playthrough in Grey Matter
Make progress through the main game in Time Fcuk
Come full circle in Coil
Discover the Moon of Debasa
Discover the Moon of Earth
Discover the Moon of Gravida
Discover the Moon's of Bibulon
Discover the Moon of Malaisus
Find the lost spaceman
Find the runaway
Find the Lost Bird
Find the Crybaby
Find the Paradox
Find the Skinless Boy
Find the Glutton
Find the Demon
Finish the Game
???
Complete Spewer Chapter 1
Complete Spewer Chapter 2
Complete Spewer Chapter 3
Complete Spewer Chapter 4
Complete Spewer Chapter 5
Complete Spewer Bonus Chapter
Create and play a custom level in Spewer
Make more progress through the main game in Time Fcuk
Make even more progress through the main game in Time Fcuk
Complete the game the right way in Time Fcuk
Complete the game the wrong way in Time Fcuk
Complete chapter 2 in Time Fcuk
Complete the Unknown in Time Fcuk
Create a level in the editor in Time Fcuk
Beat Mormal Mode in Grey Matter
Beat Expert Mode in Grey Matter
Beat Boss Rush in Grey Matter
Get XXXXX points in one playthrough in Grey Matter
Complete chapter one in Meat Boy
Complete chapter two in Meat Boy
Complete chapter three in Meat Boy
Complete bonus chapter in Meat Boy
Collect 16 bandaids in Meat Boy
Collect 4 bandaids in Meat Boy
Collect 8 bandaids in Meat Boy
100% Meat Boy
Complete Triachnid
Find and collect all the lost larva in Triachnid
Unlock all bonus content
100% the basement collection