Sett

Sett is a reconstituted demon, summoned by Incognito using Integra's blood. It's never explicitly stated, but as Tubalcain, it is implied that he is Seth, the son of Adam and Eve. Though referred to as a demon in the dub, in the Japanese version Integra refers to it as "Jashin Seto", or "The Wicked God Sett", implying this heavily; Incognito later says he wields the power of an Ancient god as well, referring to Sett. However, considering Ingonito's connection to the 'Dark Continent' (better known as Africa), this might be refering to the Egyptian deity known as Set.

Appearance
Sett appears as a streak of white light, moving through London destroying everything in its path, and was absorbed into Incognito's body as part of his ritual.

History
Sett made its first appearance after Incognito does a ritual in the Tower of London on Integra, and his ritual was successful, summoning Sett who causes chaos on England, destroying everything in its path until, Alucard was revived and in its final and most powerful form. Incognito later orders Sett to aid him in his battle with Alucard, who Sett tries to bite. Alucard casually holds Sett's mouth and taunts Incognito when Sett blasts him and later, when Alucard spawns Baskerville which bites onto Sett, it causes a shock wave which sliced buildings and even towers, clean and sends both Alucard and Incognito up above the clouds where they battle.

Incognito fuses with Sett and was seen damaging Alucard's eyes and then, after a short battle, they clashes, which sends another shock wave and made both Alucard and Incognito fall and impacted a Cathedral after their fall from the sky, their collision lit up the entire building on fire from the inside. Sett was later seen merging with Alucard and Alucard's hair begins to glow white and holds onto a Silver cross behind him and melts it onto his broken Jackal, which he uses to impale Incognito after making a really long bullet. What happens Sett after merging with Alucard is unknown.

Abilities
Sett also breaks the boundaries of Dark Magic, meaning he can increase the user's power to maximum allowing them to break their Dark Magic limits. Incognito used its power to fight Alucard in his level 1 form, but it proved to be insufficient and Incognito was killed. Although a god, he is not powerful enough to kill Alucard. Sett's fate after Incognito's death is unknown, however, it is assumed that Alucard gain Sett's ability, therefore, just like how Baskerville became Alucard's servant, it can be safely assumed that Sett is, too.

Trivia

 * Sett is probably, or is based on the Egyptian deity known as Set.