Eyghon's History
Summoning
In 1975, Eyghon's existence was discovered by a group of young sorcerers in London who practiced magic for pleasure and gain. Its members — Rupert "Ripper" Giles, Ethan Rayne, Randall, Thomas Sutcliffe, Deirdre Page, and Philip Henry — tattooed themselves with Eyghon's mark and summoned the demon. Their intention was to take turns sleeping while the rest would invoke Eyghon to possess the sleeping participant, resulting in an "extraordinary high" for the one possessed.
The possession, though, resulted first in the death of Randall, despite Ripper and Ethan's attempt to exorcise him. The demon promised to dominate them and the Earth, remembering that they had his mark and he owned their bodies and souls.
Hunting Giles
By late 1997, Eyghon had already killed Thomas, then Diedre, whose corpse he took possession of to hunt down Philip. Eyghon chased Philip to Sunnydale High School, where Philip had gone to find Giles about twenty years after their last encounter. However, Eyghon killed Philip before the latter could reach Giles and took possession of Philip's body.
Eyghon awoke at the morgue and attacked an attendant. He then tracked Ethan through the tattoo in the warlock's forearm, finding him in the Sunnydale High School library. There, the Slayer Buffy Summers incapacitated Eyghon and locked him in the library's book cage. However, Eyghon managed to break out of the cage as Philip's body was about to collapse, and he took possession of one unconscious person he could find: Jenny Calendar.
Giles took Jenny to his apartment, where the demon manifested and tried to kill Giles. The Slayer interrupted him, but Eyghon escaped. He went after Ethan in his abandoned shop, but Eyghon did not attack him as Ethan had removed the demon's symbol from his skin with acid. Eyghon then turned to Buffy, whom Ethan had tattooed with Eyghon's mark. Eyghon and Buffy fought until Giles interrupted them by offering himself in place of Buffy.
The demon tried to kill Giles, but Angel intervened and began to choke Eyghon. In danger of dying, Eyghon jumped from Jenny to the closest "dead" body — that of Angel. However, Eyghon hadn't counted on Angel being a vampire, and he had to face the demon within. The two demons fought inside Angel, and Eyghon was defeated and expelled from Angel's body, disappearing.
Return
Despite his apparent death, Eyghon had escaped by possessing the body of a dead rat underneath the shop's floorboards. He then possessed a homeless man unconscious in the street, from which the demon eventually emerged in the physical world.
With the death of Ethan and Giles, Eyghon reclaimed their bodies using other possessed servants, having taken in their souls after their deaths. Reanimated, the possessed Ethan needed to wear a hat to conceal the bullet hole that had killed him, while the possessed Giles had his neck twisted where it had been broken in his death.
Since Eyghon could draw on the inner natural magic of others to create his army, he formed an alliance with other demons, including Whistler, Pearl, and Nash, to try and restore magic using accumulated magical artifacts to trigger a magic plague; in the deal, Eyghon would gain control of a continent and billions of magic-soaked zombies to populate it after magic was restored.
Eyghon had the possessed Giles pose as an occult specialist in resurrections, requiring various magical artifacts as charges in the absence of magic. In reality, these objects were given to Whistler and his crew to create the mystical plague with their energies, and Eyghon infused those he claimed to resurrect with his essence. The possessed Giles performed phony rituals that required those who knew the deceased to talk about their memories of their lost friend, so that Eyghon could use those memories to make the false resurrection convincing and pass off other details as traumatic amnesia.
A group of Slayers in London sought "Giles" to resurrect the recently-deceased Slayer Marianne, but Nadira realized it was a fake when she couldn't remember her last name and still bore her fatal wounds. Eyghon's army of reanimated minions attacked and got some of the Slayers unconscious so Eyghon would possess them too. Meanwhile, Angel and Faith were investigating the disappearance of Giles' corpse and found Eyghon's hideout in realty recently bought under Ethan's name.
Angel realized that Eyghon was focusing his efforts on Slayers to include superpowered magic-infused warriors in his army in the case of Pearl and Nash double-cross him.[3] While Angel organized an attack on Eyghon with and Faith, Spike, and the remaining Slayer squad, Eyghon found them in Alasdair Coames' residence, attacking with his and his zombie army. Their attempts to restrain his human shield and kill Eyghon initially failed, with Eyghon possessing Spike because his previous limitations with vampires did not apply in his true form.
However, Eyghon's attempt to possess Angel failed once again, since his body was then populated with Giles' soul in addition to his demon and soul. Their triple nature allowed Angel to resist Eyghon's influence long enough for Giles to temporarily take control of Angel's body; using the Vorpal blade, he decapitated Eyghon, the only way of killing the demon.
With Eyghon's death, the piece of Giles' soul that Eyghon had retained went into Angel, conducted by the Tooth of Ammuk. The corpses Eyghon possessed fell, and those unconscious woke up.
