Here is the full list of all 30 Who Knocks achievements.
You survived the first jumpscare.
The first guest has arrived!
You fixed all the toy animals
You fixed all the dolls.
You have fixed all the weights.
You put batteries in the projector.
You fixed all the essences.
You have fixed all the spices.
You put all the figurines back.
You entered the correct combination.
You took the axe.
You took the gun.
Completed the house without taking the gun.
You took the Level 5 tile.
Collected all cassette tapes in the house.
Collected all Energy Drinks in the house.
Collected all ammo in the house.
You have awakened.
Returned Sh3v4's heart.
Put the pieces of Sh3v4 in their place.
Reassembled the puzzle.
Found the second level tile.
Found the third level tile.
Purified the ship.
Found all Digital Keys.
Collected all cassette tapes in the spaceship.
Collected all Energy Drinks in the spaceship.
Collected all ammo in the spaceship.
Found the Trophy Room.
Finished Who Knocks.