cernunnos (fate)

Fate/Grand Order character. The horned Celtic god of beasts, nature and fertility.

Huge spoilers below for Lostbelt no. 6: Fairy Realm of the Round Table, Avalon le Fay.
Originally a gentle giant, Cernunnos was poisoned by the fairies, and they used his corpse to create the Lostbelt Britain. Cernunnos slept in the Great Pit gathering curses until it was awakened late in the events of the Lostbelt, threatening to destroy the entire world.