|“||Ah, yes. Consider that mystery my last gift to you Father. I hope it drives you insane.||”|
–Trophonius to Apollo, The Dark Prophecy
Trophonius was the son of Apollo and King Erginus's wife. Agamethus was his maternal half-brother (his father was Erginus). Trophonius and Agamethus grew up to become renowned architects and built Apollo's temple at Delphi.
Agamethus's death (and Trophonius's downfall) came after King Hyrieus entrusted to the brothers the task of designing his treasury. They became greedy for Hyrieus's wealth and designed the treasury with a secret thieves' tunnel. They planned to slip into the treasury in the dead of night, steal the valuables and slip out via the tunnel.
Unfortunately for them, Hyrieus had inspected every nook and corner of the treasury and discovered the secret tunnel. He had set up a rope-activated crossbow trap to catch any thief, intending to find out who planned to rob him.
When the brothers came out of the tunnel with the treasure, Trophonius sprung the trap without realizing it. As a result, Agamethus got trapped in the tunnel, crushed under a beam. Trophonius was unable to pull his brother out. Agamethus then decided to sacrifice his life and told his brother to cut his head off and then run away. This way, Trophonius would be saved and Hyrieus would be unable to discover the identity of the thieves. Trophonius pleaded with his father to let him die instead, but Apollo, disappointed that he had chosen to use his talents to become a thief, ignored his prayer. He was forced to decapitate Agamethus before running away.
Miserable and guilt-ridden, Trophonius wandered the earth for months before he entered a cave and disappeared. One day while they were suffering a plague, the Lebadaeans consulted the Oracle of Delphi who told them about him. A shepherd boy finally found the cave when he followed bees. With the help of Mnemosyne, the boy issued a prophecy that cured the plague. Trophonius was thus turned into the Dark Oracle.
After Commodus's captives are rescued, Emmie and Josephine try to put their adoptive daughter Georgina onto the Throne of Memory to extract her prophecy and cure her madness, but she refuses to sit until Apollo comes back. Once he is present, she speaks, but rather than a prophecy, it is a message addressed to Apollo, telling him to come with Meg to his cave the next morning. He also calls Georgina his "little sister", implying that she may be a child of Apollo.
When Meg McCaffrey and Apollo arrive at the cave, Meg begins to pour her feelings out in the cave, attempting to keep hundreds of water snakes at bay to save Apollo. This allows Trophonius to give her the prophecy, and he mocks Apollo despite the latter begging to take him instead, then he sends bees to attack both of them. After Apollo gives Meg CPR to ease her suffering, the spirit of Trophonius asks Apollo to blow up the oracle because he doesn't want to be used by Commodus anymore. He says he might appear in another cave in the next hundred years or his spirit will be put to rest.
Trophonius is bitter and resentful after his half-brother Agamethus' death, and much of this anger is directed towards his father, Apollo, who refused to help him save Agamethus at the time of his death.
During Apollo's flashback of his escape from King Hyrieus, Trophonius had lustrous dark hair like his mother. With Apollo being his father, he had a muscular physique and handsome face with a strong chin, perfect nose, and rosy lips.
However, when Trophonius appears in his cave he is an apparition that was only vaguely humanoid, composed of shadows and fractals of light. He still has his lustrous dark hair and proud face though.
- Trophonius' name means "Nourisher of the Mind".
- His sacred animal is the bee.
- Trophonius is the only one of Apollo's four oracles that is male.