Fenris

The Strucker Twins' DNA was altered by their father Baron von Strucker while they were still embryos. The twins are white supremacists and strive for the resurrection of the Fourth Reich.

The Strucker twins despise Magneto for his role in their father's supposed death some years after World War II. They later attack Magneto during his trial in Paris by the International Court of Justice for his crimes against humanity. The X-Men eventually stop the duo from attacking Magneto, but they manage to escape into the sewers.

The Strucker twins have encountered Storm of the X-Men, in which Storm stops Andrea's assault on a native woman in Africa. Andrea gets revenge for Storm's victory by shooting her in the head and then leaving her to die.

Fenris later resurface as part of the team called the Upstarts, a group of mutant millionaires controlled by Gamesmaster and Selene, the Hellfire Club's former Black Queen. They engage in a campaign of mass murder as part of a game organized by the mutant telepaths. The twins try to recruit Omega Red for the Upstarts but fail to do so. Fenris finally met their match when they tried to kill the former New Mutants member, Wolfsbane. Wolfsbane with her new X-Factor teammates easily defeats the pair.

After their defeat Fenris join a group crime lords who intended to divide up the empire left by the defeated Kingpin. The Crime Lords consisted of Slug, Hammerhead, Tombstone and their own sibling Werner von Strucker.

The twins didn't believe that Werner was their brother, and this conflict caused the meeting to degenerate into a fire fight. The twins tried to kill Hammerhead but he was eventually rescued. Werner is killed by their own father who was disguised as one of his assistants. Baron Wolfgang Von Strucker later recruits the pair into his organization. The team fights the new Citizen V, until Andrea discovers that he is actually Baron Zemo.

Baron Helmut Zemo is then decapitated by Nomad under orders of Henry Peter Gyrich. Techno then transfers his mind into the comatose body of the second Citizen V, (John Watkins III). Andrea is killed by Zemo to keep his secret. Andreas, distraught after his sisters death, takes the identity of the new Swordsman and joins the New Thunderbolts. Disturbingly, by tanning his sister's skin and attaching it to his sword, he is able to keep the powers he shared with her as a part of Fenris. Andrea later returns but is revealed to be a clone created by Arnim Zola, who Andreas had contracted him to do so. Director Norman Osborn is concerned at the speed at which she had been cloned.

Fenris and the Thunderbolts go into battle against the Skrulls during the Secret Invasion and they witness Moonstone after she takes out Andreas and attempts to make a deal with the Skrulls. Andrea then attacks Moonstone but while distracted, Bullseye kills her from behind. Andreas later confronts Osborn because he was not offered a place in the roster of the new Dark Avengers. Andrea also found out that Norman had never planned to fulfill his vow to resurrect Andreas or provide them with a full presidential pardon after his time with the Thunderbolts ends. Norman then kills Andreas with his own swords and dumps him out a near by window.