Andrea and Andreas are the children of
Hydra leader
Wolfgang von Strucker. While the two are still in their mother's uterus, they are genetically modified by
Arnim Zola. This gives them bio-energy powers which they can use when in physical contact with one another, usually when holding hands. Strucker indoctrinates his children in the beliefs of
white supremacy,
Nazism, and the
Fourth Reich. In adulthood, the twins become the
supervillains known as Fenris and lead the terrorist organization of the same name. Like their father, they are white supremacists. The Strucker twins go up against
Storm when Storm interrupts Andreas's attempted assault on a native woman in Africa. Andrea retaliates for Storm's humiliation of Andreas by shooting her in the head and leaving her to die. The twins join a conference of powerful criminal leaders who intend to divide up what is left of the
Kingpin's fallen empire. Among the members of the conference are
Slug,
Hammerhead,
Tombstone, and
Werner von Strucker. The twins do not believe that Werner is actually their sibling. This and other arguments cause a fight to break out in the conference room. Fenris attempts to kill Hammerhead, who is rescued. Their sibling is later killed by their father attending the conference disguised as Werner's assistant. The twins resurface and are seen working with Baron Strucker. They fight
Citizen V, who Andrea discovers is housing
Helmut Zemo's mind. Zemo kills Andrea to keep her from telling anyone the truth. After Andrea's death, Zemo has
Purple Man brainwash Andreas into taking the alias of "
Swordsman". Purple Man has Andreas remove Andrea's skin and incorporate it into his sword, allowing it to channel their shared powers. Andreas breaks free of Purple Man's control and joins the
Thunderbolts. Teammate and field leader
Moonstone approaches Andreas with an offer: if he helps kill
Songbird, Moonstone will be able to make a move to usurp
Norman Osborn, the Thunderbolts' director. Under the control of four imprisoned telepaths, Andreas takes over the title of "Baron Strucker" and shaves his head in his father's honor. He gains the loyalty of guards by paying them well and orders them to set off a bomb in the
Zeus, the Thunderbolts' carrier, to initiate a lockdown. Andreas declares to one of his guards that Osborn will bring him back his sister or everyone in Thunderbolts Mountain will be killed. After most of his guards are killed, Strucker kills off the remaining attacking guards. He then encounters
Venom declaring to eat Strucker. The two fight and Strucker runs Venom through with his sword. Osborn snaps and attacks Andreas,
crucifying him to a wall with his daggers. Andreas survives Osborn's attack and later learns that Andreas had Arnim Zola create a clone of his sister. Although Andreas has Andrea back, he wants to complete his Thunderbolts contract, leaving as a free man. To protect Andrea while on missions, Andreas skins his arm, giving the flesh to Andrea to hold and allowing her to use their shared powers. Andrea accompanies Andreas and the Thunderbolts during the
battle against the
Skrulls. After Moonstone incapacitates Andreas and attempts to make a deal with the Skrulls, Andrea attacks Moonstone, but is killed by
Bullseye. Andreas confronts Osborn with the revelation that he was not offered a slot on the
Dark Avengers, as well as never planning on resurrecting Andrea or receiving a pardon. Osborn has a moment of insanity and stabs Andreas through the chest with his own sword, apparently killing him. Through unspecified means, Andrea's clone and Andreas are resurrected and open "Club Fenris", a supervillain club in
Manhattan. They are also residents of the
mutant nation of
Krakoa. As part of the Hellfire Trading Company, the Fenris twins operate as the Black Knights. Fenris attacks
X-Corp and escapes, with
M planning to have them thrown into the Pit of Exile if they are ever found.
Orchis later contracts the Fenris twins to poison Krakoa with Blightswell and open the Pit of Exile to free
Sabretooth. They are defeated by
Bishop and his War College and remanded to the Pit. During the "
Fall of X", the
Hydra Supreme version of Steve Rogers recruits Fenris to join the
Mutant Liberation Front. ==Powers and abilities==