[b]The Thirteen Seekers of Darkness:[/b]

Leo, Kixham, False Hakim and Young Leo, - Planet Busters, as they should have been.
Philippa (Element of Borders) - Able to create enclosed spaces where she can alter one rule of reality as she sees fit. She uses this to create zones where gravity is increased or decreased, where humans cannot breathe oxygen, or where certain types of Magic are stronger or weaker. Her main weakness is that if her 'border lines' are broken, her zones are destroyed.
Baron Carlstein (Element of Munny) - Very game-breaking, as he is able to control Munny to form monsters made of it, magically transfer spells and curses through units of munny, know what anyone who has Munny on him is doing, and of course, break entire economies with a spell. I might actually make him a neutral party this time around, so that he does not magically kill the PCs by transferring a Death Spell through their coins.
The False Angel (Element of Dark and Light) - Self-explanatory.
Horus Luprecal (Element of Chaos) - Self-explanatory, and he is one of the few Seekers to actually be nerfed.
Lavinia (Element of Agriculture) - Can summon and control animals and plants, farming equipment like tractors, and various forms of flammable liquor. Can instantly cause famine to entire countries.
Mr. House (Element of Technology) - Self-explanatory, but cannot control Magitech. Very powerful.
King Herod: Yes, that King Herod (Element of Usurpation) - Can use one spell or technique from each of his opponents, which makes him a powerful opponent.
Simo Hayha (Element of Space) - No, he is not the Xigbar-equivalent.