Here is the full list of all 30 Candle Prick achievements.
Unlock the palette editor
Get the letter C
Get the letter A
Get the letter N
Get the letter D
Get the letter L
Get the letter E
Unlock the CAKE palette
Unlock the CORRUPT palette
Unlock the DEERSKULL palette
Unlock the ERROR palette
Unlock the GAMEKID palette
Unlock the HYPER palette
Unlock the JULIA palette
Unlock the KING palette
Unlock the MENGAS palette
Unlock the NIGHT palette
Unlock the NOIR palette
Unlock the RESIDENT palette
Unlock the RUINS palette
Unlock the TENTH ORBIT palette
Unlock the TWILIGHT palette
Unlock the WARP palette
Unlock the WISP palette
Finish the game
Beat all levels
Unlock all palettes
Blind yourself
Get stabbed
Unlock the CYBERBOY palette