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