Here is the full list of all 21 TETRA's Escape achievements.
Save at least 200 Tetras (sum)
Dead by fall before level explanation
Walks over 2500 boxes (sum)
Complete a level without any stars
Complete the 6th world
Burn all tetras in the same level
Complete the 5th world
Get half the cups
Complete the 4th world
Get half the stars
Save at least 100 Tetras (sum)
Complete the 3rd world
Walks over 1000 boxes (sum)
Get a quarter of the cups
Complete the 2nd world
Get a quarter of the stars
Complete the 1st world
Change all Tetras in a level into tetrominos and lose...
Save at least 10 Tetras (sum)
First transformation into tetromino
Get first cup