The mutant speedster Quicksilver (aka Pietro Maximoff) got a fake replacement in the MCU's WandaVision, as actor Ralph Bohner was forced to trick Wanda Maximoff into believing he was her resurrected brother. However, in the comics, Quicksilver actually invented a fake replacement in the greatest twist of the hero's long and stories career.
After encouraging his sister the Scarlet Witch to alter reality and create the mutant supremacy called House of M, Quicksilver lost his powers when Wanda cast the infamous«no more mutants» spell and caused M-Day. Thanks to his connections to the Inhumans (Pietro's ex-wife, Crystal, is a member of the Royal Family, as well as their daughter Luna), Quicksilver learned that the Terrigen Mists had the potential to restore mutants' powers, but at great risk. Wanting to atone for his sins against mutantkind, and driven by growing depression and self-loathing, Pietro stole the Inhumans' sacred Terrigen Crystals, gained the power to time-travel, and started on his foolish quest to save mutantkind. Increasingly deranged, Pietro did not realize he was killing more people than he was saving, and he had to be stopped by the Inhumans and his former teammates in X-Factor.
Related: Marvel Comics Finally Gives Quicksilver His Due
Quicksilver really hit rock bottom during that period, ending up in jail for vagrancy. However, when he realized he had fully recovered his mutant powers, he tried to be a hero once again and joined the Mighty Avengers. Pietro needed to clear his reputation, so he went on TV and took advantage of the recent Skrull Secret Invasion, stating that all of his villainous actions had actually been performed by a Skrull impostor (this happened in The Mighty Avengers #31, by Dan
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