Here is the full list of all 40 Relicta achievements.
The base game contains 27 achievements, and there is 1 DLC pack containing 13 achievements.
Run away with Kira
Stay and wait for Ragnar
Complete all puzzles of Relicta
Complete all puzzles of Sverdrup dome
Complete the second area of Sverdrup
Complete all puzzles of Faustini dome
Complete the second area of Faustini
Complete all puzzles of De Gerlache dome
Complete the third area of De Gerlache
Complete all puzzles of Shoemaker dome
Complete the third area of Shoemaker
Meet the parasite
Complete the first area of Sverdrup dome
Find 50% of PDA data cards
Activate the antenna to contact Ragnar
Complete the first area of Faustini
Find 50% of collectibles
Complete the second area of De Gerlache
Complete the second area of Shoemaker
Complete the first area of Shoemaker
Find a PDA data card
Find a collectible
Complete the first area of De Gerlache
Complete the prologue
Find all collectibles
Find all PDA data cards
Complete Relicta in less than six hours
Use the magnetic abilities for the first time
Complete all the puzzles of the day
Complete eight puzzles
Complete four puzzles
Complete the first puzzle of the day