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