Here is the full list of all 53 Supraland Six Inches Under achievements. It takes around 15-20 hours to unlock all of the achievements on Windows.
I can fly... for a very short moment
So much industry
You are less lost
You're so attractive
Purple lines
This one will never break
Hello there!
Defeated Surprise Chest
Cage Town
Killed the ghouls
It's made of wood, it will last forever
Jump Higher!
Bending the knee gets you further
Hit Rock Bottom
Run faster
He did all the work
You're halfway through the game already
Heated up the water
Excellent plumbing work
You were hoping you would never see him again
Brings back the good old economy
Made it to the 2nd floor
Get an accountant
You're a criminal
Gold Module
Lifting weights
Broke into the bank
Bzzz bzzz
Very secret!
Improvised
Much boom boom
I used to get the earlier in the previous game
Flying, sort of
Saved it from exploding
He loves the ladies
You feel so OP all of a sudden
Beat the big guy
Very unrealistic
You're probably 50% done now
Beep beep
The kids liked it
It feels so stable
Not sure if it's just a blue stone pickaxe
You feel way too OP now
Burn 'em all
Boing
You smell so nice
And all I got was this lousy chest
Beat the arena next to town
Don't look behind you
Left the level
It probably has no use
Much secret!