Vortigern Oberon is a complex antagonist in the mobile game Fate/Grand Order. As the Fairy King in the Lostbelt No. 6, Avalon le Fae, he presents himself as a mysterious and whimsical character, with an enigmatic demeanor that keeps other characters guessing about his true intentions. Oberon is known for his deceptive nature, often manipulating events to suit his own purposes. Despite his seemingly playful and carefree attitude, he harbors deeper, darker ambitions. Oberon's role is pivotal in the narrative, challenging the protagonists and contributing significantly to the storyline's tension and intrigue.