Here is the full list of all 13 Lunaform achievements.
Complete the Centauri Planet
Complete the Nymph Planet
Complete the Coran Planet
Swap 100 times
Bump 1000 stars
Complete the Lunaform Tutorial
Complete the Slyph Planet
Complete the Luna Planet
Complete the Blackhole
Shield from 100 stars
Beat Centauri3 without taking any hits
Unlock all the upgrades
Fill every Hex