Here is the full list of all 15 bit Dungeon II achievements. It takes around 2-3 hours to unlock all of the achievements on Windows.
Free the ghost from her grave.
Slay the Demiurge.
Tis this a demon?
Slayed the Fiend.
Enter into the Dark World.
Slay the Fire Nob Glob.
Face The Eater!
She rules an army of beasts in the Black Church, defeat The Yaldabaoth.
Kill the king of Skeletons.
You have died. You have all lost things. You can not take your possessions with you to the next incarnation.
Kill the leader of the Thief Kings, The Cursed Wizard!
Destroy the Soul Collector.
Find an epic-quality weapon.
Reach level ten.
Kill a mini-boss.