Here is the full list of all 24 The Impregnation of the Elves: Conquest of the Arrogant Fairies by Impregnation achievements.
Defeat all the Elves in Challenge Mode
Passed a question once
Unlock all achievements
Achieved Ending 2
See the Goddess' True Form
Defeated by Idun
Defeated by Frigga
Victory over Frigga
Victory over Nimue
Defeated by Nimue
Defeated by Dryad
Victory over Vivian
Defeated by Vivian
Victory over Nineve
Defeated by Nineve
Victory over Dryad
Destroy Idun's armour completely
Destroy Frigga's armour completely
Destroy Nimue's armour completely
Destroy Vivian's armour completely
Destroy Nineve's armour completely
Destroy Dryad's armour completely
Achieved Ending 1
Victory over Idun