Here is the full list of all 15 [it's possible] achievements.
Reset your cloud save
Create over 20,000 blood particles
Die 1,000 times
Create over 9,000 blood particles
Beat the game
Die 500 times
Die 400 times
Die 300 times
Die 200 times
Die 100 times
Die 50 times
Create over 1,000 blood particles
Die 25 times
Die for the first time
Kill yourself