Here is the full list of all 18 OTXO achievements.
Destroy the Heart
Vault over 50 times
Kill an enemy with a thrown magazine
Collect all guns
Kill 50 enemies with grenades
Kill 15 enemies with doors without dying
Go fishing
Play fetch
Order the ANIMAL drink at the bar
Roll over 100 times
Clear a room without using Focus
Die for the first time
Collect everything from the gachapon machines
Clear a room by only kicking
Clear a run on Impossible Mode
Kill 50 enemies with kunai
Unlock all drinks
Clear a full run without taking any drinks