Hello, who are your favorite forgotten villains ?

So far, I have found :

(1) Three villains who could have become main characters :

- The Madman, Hulk archenemy, brother of Leader (dead or not dead, that is the question ?)
http://marvel.com/universe/Madman_%28Phillip_Sterns%29
("reverse Hulk")

- Hunter the White Wolf, adopted brother of Black Panther (still active)
http://marvel.wikia.com/White_Wolf_%28Hunter%29_%28Earth-616%29
("reverse Black Panther")

- Insomnia, sleepless agent of Mr Fear with superhuman vision (still active)
http://www.marvunapp.com/Appendix/insomniadd.htm
("reverse Daredevil")

(2) Two interesting femmes fatales :

- De'Lila, rogue Skrull agent with a psychic seduction power, who was able to trick Wolverine, Spider-Man, Hulk and Ghost Rider to help her (unknown fate: prison or death penalty)
http://www.marvunapp.com/Appendix/delila.htm

- Sapphire Styx, psychic vampire mutant, enemy of Wolverine (unknown fate : dead ?)
http://www.marvunapp.com/Appendix2/sapphirestyx.htm

(3) Two spider-man villains who don't appear anymore, even if longtime readers know them :

- The Foreigner (still active)
http://en.wikipedia.org/wiki/Foreigner_%28comics%29

- Carlos Lobo, one of the Lobo brothers (prison)
http://marvel.com/universe/Lobo,_Carlos

(4)Two characters once used by Peter David but who may be dead :

- Mister Frost, one time enemy of the Hulk (self-exploding, perhaps dead ?)
http://marvel.com/universe/Mr._Frost

- Snow Queen, one time enemy of Wolverine (dead in the explosion ?)
http://www.marvunapp.com/Appendix/snowqunw.htm

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