Warning: SPOILERS for House of X and Powers of X
Jonathan Hickman's X-Men relaunch appears to center in on a retcon that simply doesn't work. Marvel's latest attempt to relaunch the X-Men comics features superstar writer Jonathan Hickman (Fantastic Four, New Avengers, Secret Avengers). He's put together a years-long story that kicked off with the House of X miniseries, which is intended to reinvigorate the entire X-Men range.
Hickman loves to throw readers as many curveballs as possible, and as a result House of X #2 centers in on the story of Moira MacTaggert. The comic book version of Moira is, of course, very different to the character movie fans know from X-Men: First Class. In the comics, Moira is traditionally viewed as a human geneticist, a former lover of Professor Charles Xavier, and the winner of a Nobel Prize because of her work on genetic mutation. Hickman, however, has just retconned all that away... revealing Moira MacTaggert isn't actually a human being at all.
Rather, Moira is a mutant, gifted with the power of reincarnation. Every time Moira dies, her consciousness returns to the moment of her birth, and she is born retaining all the knowledge from her past lives. Furthermore, Moira possesses a natural defense mechanism that makes her invisible to other mutants. It's one of the biggest retcons in X-Men comic history, affecting a secondary character who's played a vital role in the X-Men comics since 1975. But there's just one problem; this retcon makes absolutely no sense at all.
The fundamental problem with this retcon is that Moira MacTaggert is the one human character in the Marvel Comics universe who simply can't be a secret mutant. In the 1990s, Moira MacTaggert was at the forefront of the battle against a deadly disease that was affecting the mutant population, the Legacy Virus. Tragically, in Excalibur #80 Professor Xavier realized that the Legacy Virus had actually mutated, and could now affect humans as well as mutants. He learned this because his beloved Moira MacTaggert was the first human to be diagnosed with the Legacy Virus. What's more, the comic made it abundantly clear that Moira had provided a sample of a mutated virus. As a result, Moira's DNA was studied in detail by the greatest minds on Earth, as they attempted to figure out why the Legacy Virus had mutated and affected her. When Moira's condition finally became public knowledge, she was heartbroken to see the chaos it caused, as anti-mutant riots blazed across the globe for fear of the Legacy Virus spreading to humans.
There's nothing fundamentally wrong with a retcon; even Marvel Studios has them, retconning Captain Marvel into the history of the MCU as the inspiration for the Avengers. But a retcon is a tricky thing to pull off, simply because it can be difficult to align them to previous canon. Usually you wind up choosing to selectively ignore minor plot elements from older comics in favor of the retcon. Moira's Legacy Virus arc, however, is no small matter; it became a fundamental part of her comic book story for several years, and ultimately culminated in her death at the hands of Mystique. This is one of Moira MacTaggert's most important stories.
At the moment, the only possible way of reconciling this is to suggest that Moira faked the whole thing; that as a mutant she was susceptible to the Legacy Virus, and that she faked the virus' mutation in order to keep her secrets. If that's the case, then she led all research into the Legacy Virus down an intellectual cul-de-sac for months, potentially delaying the development of a cure, and is responsible for the deaths that happened in the meantime. Furthermore, her lies would also make her responsible for the anti-mutant riots, and all the people killed in those too. This idea would just about make the retcon work - but it would destroy Moira MacTaggert as a character, turning her into one of the most duplicitous, self-serving figures in the X-Men comics. That's almost certainly not what Jonathan Hickman intended.
House of X #2 is on sale now from Marvel Comics.