Sebastian Blood

"You know who he is under that hood. Don't you?"

- Sebastian to Slade

Sebastian Blood, also known as Brother Blood, is an alderman and undercover cult member who rose to power following The Undertaking. He supposedly blames the Queen family for the destruction of the east sector of the Glades. However it is revealed in "Crucible" that he heads an evil cult hell-bent on taking over Starling City. In "Three Ghosts" it is revealed that Sebastian's superior is Slade Wilson. He is one of the two main antagonists of Season 2.

Biography
Sebastian was raised by his mother and an abusive father. One day, his father came home drunk and had attacked his wife and child. Sebastian had taken his father's gun and killed him. As the police arrived, he had his mother commited to an asylum and became orphaned. Growing up in an orphanage, Sebastian encountered a priest named Cyrus Gold who promptly became like a father-figure to him.

Season 2
In "Identity",

In "Crucible", Sebastian helps Oliver to set up a "guns for money" fundraiser for people affected by both the earthquake, and gun violence in The Glades, to reduce the increased gang activity (due to "The Mayor" rising to power as a gang leader), but is shot at, along with the crowd during the event by "The Mayor"s' men.

After The Mayor is arrested, a corrupt police officer takes him to Sebastian, who wears a mask and administers the unwilling Mayor with a serum he calls "The Miracle". The precise effects of The Miracle are unknown, as are Sebastian's true intentions, but the serum caused The Mayor's eyes to bleed before possibly killing him. After injecting The Mayor, he instructs the officer to find him "another". The officer addresses him as "Brother Blood".

In "State v. Queen", it is revealed that he provided Count Vertigo with a means to redistribute his product, as he knew that it would flush out The Arrow so that Count Vertigo would kill him. Upon finding that The Arrow killed Count Vertigo rather than the other way round, he is initially angry, until he is informed that the first test subject has survived (or possibly awakened from) his exposure to the Miracle.

In "The Scientist", Sebastian was getting regular reports from Daily about movements conducted by three people looking into one of his test subjects, Maxwell Stanton's death. Sebastian gave Cyrus Gold locations of where to strike; Queen Consolidated's applied sciences division and a blood bank which were necessary for making more Miracle.

In "Three Ghosts", Sebastian learns from Daily that the police are planning to go after Cyrus Gold and sends Cyrus to confront them. Meanwhile, in his civilian guise, he romances Laurel Lance, taking her Christmas shopping, and announces his campaign for mayor of Starling.

Sebastian has his subordinate inject a captured Roy Harper with The Miracle. When The Arrow appears, Sebastian orders Cyrus to kill him; Cyrus is defeated and Sebastian flees. He meets with Slade Wilson, who is revealed to be Sebastian's employer and the true mastermind behind the Blood Cult.

In "Blast Radius", Laurel comes to his office, questioining him about his past. Sebastian reveals that his father came back home drunk and his mother then killed and promptly abandoned him as the police were coming. Cyrus was became a father-figure to Sebastian when he became orphaned. As Laurel continues to investigate Sebastian, she visits his aunt, Maya Rezik, who is locked up in an insane asylum and Sebastian is paying to be cared for. As Laurel asks her about her nephew, Maya reveals that she is actually Sebastian's mother and begins to refer to him as the devil.

Personality
As an alderman, Sebastian has shown himself to be charismatic, thus able to win crowds and win support to the point where Starling City wants him to become mayor. As a cult member, he kidnaps victims and injects them with The Miracle, and if they survive, forces them to work for him. He is also evil and ruthless.

Abilities

 * Popularity: On Sebastian's alderman side, he is popular, as Starling City wants him to become mayor. He has shown to be capable of winning positive attention.
 * Commanding: As a secret cult member, Sebastian is more evil and ruthless, as he captures criminals and injects them with The Miracle. If they survive initial injection, he forces them to work for him. This could be a vigilante type thing, as he believes he is saving the city with Miracle.

Equipment

 * Brother Blood costume: Sebastian wears a costume as his villain alter-ego, Brother Blood, to hide his identity from his victims.
 * Brother Blood Mask: Sebastian wears a skull mask as his villain alter-ego Brother Blood, to hide his identity from his victims.
 * Voice filter: Sebastian uses this device to change his voice regardless of who he spoke to as Brother Blood.

Season 2

 * "State v. Queen"
 * "The Scientist"
 * "Three Ghosts"
 * "The Scientist"
 * "Three Ghosts"

Trivia

 * In the comics, Brother Blood is the leader of the "Church of Blood", a cult that worships the demon warlord Trigon. He is a recurring enemy of Trigon's daughter Raven, and her friends, the teen hero group The Teen Titans.
 * There have been multiple men who have carried the name "Brother Blood". However, Arrow's version of the character carries the name of the last Brother Blood prior to the New 52, named Sebastian.
 * Sebastian is revealed to be allies with Slade Wilson who gives him blood samples to make Miracle.
 * It has been implied that since how much his campaign involves blood, Sebastian's surname is an alias.
 * In "Three Ghosts", it is revealed that Sebastian, was Behind Mayor Altman's assassination.