Here is the full list of all 34 LOEK achievements.
The base game contains 25 achievements, and there are 2 DLC packs containing 9 achievements.
Complete Level 1
Complete Level 2
Complete Level 3
Complete Level 4
Complete Level 5
Complete Level 6
Complete Level 7
Complete Level 8
Complete Level 9
Earn a bronze medal
Earn a silver medal
Earn a gold medal
Gather all gold medals
Complete the secret puzzle level
Kill the menu cow
Protect Mark's cows
Complete the Stefan bonus level
Complete the Basket bonus level
Reach a score of 100k in the Bulletcow bonus level
Complete Ballsplit bonus level
Defeat the pink helicopter
Pay $100k to open the golden door
Find all miniature cows
Jebaited
25-0 vs SphereicalBot in DIABÖLIK
Clean Dab-boi's room
Defeat Mr Sausage
Go to the weeb rehab
Complete the Potat bonus level
Complete the cow popper bonus level
Wack 'em
Reach bloxcraft
Gain access to the LOEK door