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