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