Here is the full list of all 25 Just A Dream achievements.
Conquer Anxiety
Conquer Despair
Conquer Fear
Conquer You
Hit an invisible reaper
Reach Fear
Kill 5000 enemies
Accumulate 1000 gold
Unlock an ability
Hit a bat with a grappling hook
Kill a mage with fire
Conquer You as You
Discover and use every Risk
Unlock a legendary ability
Unlock a character skin
Die to a boss with less than 1% health left
Wake up
Conquer Despair without getting hit by a single explosion
Conquer Fear without getting hit by a single chain
Unlock every ability
Use every weapon
Conquer Fear with Risk of Magic
Conquer You in less than 15 minutes
Conquer You with 4 active abilities
Defeat You with the 4 default abilities