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