Full list of all 33 Sixty Four achievements.
The base game contains 32 achievements, and there is 1 DLC pack containing 1 achievements.
Get some Reality
Dig down 64 km deep
Get some Void
Play for 64 hours
Get 64 000 000 stones
Put two silos together
Click a cookie
Get a Hollow Stone
Get some Celestial Foam
Dig down 6400 meters deep
Find a Chromalit
Destroy 64 machines
Build 64 machines
Click a cube 6400 times
Find a Hell gem
Dig down 640 meters deep
Get Beta-Pylene
Get Qanetite
Get 64 000 stones
Dig down 64 meters deep
Get some Elmerine
Stare into the abyss 64 times
Get 64 000 000 000 stones
Get stuck in the beginning
Have 9 Hell Vaults
Explode the Inverse Chasm
Honk 64 times for no reason
Have 9 Excavating Channels
Teleport 64 times
Finish the game without deleting anything for 5 minutes and having less than 15 Containment Silos
Get a Hell Gem within the first 64 minutes from the start
Reach a depth of 6400m within 6 minutes of placing a fresh Excavation channel
Complete the game without ever upgrading extraction channels