I've been meaning to blog for a while on Quicksilver's mental breakdown, mainly to answer fans who think that there's no fixing House of M, Son of M, and Silent War without a Skrull or possession explanation. Really, there's a number of points in the storyline that a writer can seize on and use to exonerate him without pulling in a new mind-controlling villain into the mix or saying it was an imposter. I don't know if Bendis or Hine put them in there on purpose, but they're there and I think Peter David at least saw a couple.
In the first place, the already accepted explanation for his complete breakdown is a pretty fucking good one. In House of M he's portrayed as a good but extremely foolish man. Bendis is actually sympathetic to the twins. He makes Pietro play the villain not by setting things up to get everything he wants (like he could), but by setting up a place to hide his sister and sacrificing his own happiness. He gives his father the benefit of the doubt and convinces his sister that Magneto could be a good guy if he had nothing to be afraid of. He gives up his own independance and becomes the obediant, adoring son his father has always demanded. The end result? The old man crushes him to death, he gets resurrected by Wanda (which, judging by Hawkeye's odd behavior afterwards, probably has a temporary effect on the brain chemistry) and awakens the next day to discover that his sister has left him, taken his power, and taken the powers of 99% of his species.
Thing is, I have run into fans that don't think this is enough. That's okay, because there's quite a bit more going on here.
I actually like the first issue of Son of M, because they play this up really well. He's dejected, miserable, powerless, blames himself for M-Day, and when he finally looks past himself to realize just how much harm he did when he was trying to help he finds it so painful he throws himself off a building. Hine really manages to put forward just how depression he's in at the beginning, so when Spider-man's tirade puts him over the edge to self-harm it doesn't seem out of nowhere or a sudden attempt to get sympathy for the character. It seems like this is a person who is that depressed, albeit because of his own actions.
Hine paints a sympathetic portrait of a man becoming a monster, but he doesn't ever call back to the fact that Pietro's a good man. He just has the events unfold and gives us Pietro's view of himself and others during this time. That's actually what ends up ringing false. Pietro is believable in a sickening way when you've been reading him up to this point, but if Son of M #1 was your first exposure to the character you'd think he was always self-centered and short-sighted rather than suffering from an incapacitating bout of depression and that this was him finally getting the results his actions were going to lead to. Crystal's statements, and part of why I hate her so badly in this, suggest that he always had a selfish dark streak and that that was what dissolved the marriage and none of her actions or even her awful uncle screwing them both over. She's an ex-wife who's bad egg of a husband has returned looking for her, and she's strong to tell him off. We're supposed to empathize with her as the virtuous partner. Luna comes off as innocently not knowing how bad her father is. Because we've read Quicksilver, we know he was a real good guy and a good father and husband who tried his best but Hine never lets us see the man Pietro was before M-Day. /He doesn't explain how a good man like Quicksilver be responsible for House of M--leading us to conclude that Pietro was a bad man (or that he has been retconned to be a bad man all along)--or explain how a good man would be driven to stealing those crystals, leading us to conclude that Pietro's nature is supposed to be a selfish bad man being revealed for once because he's lost his power.
It's really skillfully done, the mood and the pacing and the voice all support the story and character, but there is absolutely nothing even acknowledging that he hasn't always been selfish and ruthless. We have to add that ourselves as readers. There are, however, a couple of things in House of M and Son of M together that hint that he's losing it for an external reason.
There's the mood in the first issue of Son of M. There is a great cover where the artist shows everyone as moving superfast while Pietro's standing still, but inside there's a different problem. Pietro's not upset everyone else is moving fast. He's upset that he is moving slow. We know from years of characterization that Quicksilver's powers aren't just running, that he actually perceives and thinks at a greater speed than anyone else. That's why he has a patience problem. He has time to get bored in between words. If he lost all of his powers, everyone else would seem faster like on the cover. He wouldn't be able to keep up with conversations or events, everything would confuse him because it would just be going at a much greater pace than he's used to. Instead, he understands everything that's going on around him, and he perceives himself as going at a snail's pace. He doesn't see other people as going faster, he even asks how they can stand being so slow!
Whether through a stroke of brilliance or a major mistake on Hine's part (*it seems natural to paint someone as being constantly aware of their lost power but really, if he is used to having 5 times as long to process everything, he shouldn't be able to hold a conversation or react at the just slightly too slow speed he's shown reacting at), Pietro's powers are only halfway gone. FYMaximoffs on Tumblr speculated that he hadn't really lost his powers in M-Day, and was just suppressing them out of guilt. Myself, I'd been thinking that Wanda really wanted to depower her brother (thinking it would help him because as much as he loves his powers he's had a lot of social difficulties from them) but messed it up and only got it partly right, fucking his head over even more. The idea he did it himself from the trauma makes more sense, and I prefer it a lot. Whatever caused it, his powers are partially there and causing him to lose his sanity. He's lost his family and he knows it's his fault. He has only one skill, being a superhero, and he can't perform that job anymore. Then Spider-man comes along and tells him (I am not exaggerating) he has no reason to live.
Once he gets to Attilan? Hine actually establishes that someone up there fucks with his mind. This story actually excuses him for his idea to steal the Mists. The Inhumans punish the bad guy and ignore that his brain was fucked with for the umpteenth time when talking about how horrible Pietro is (like they do whenever Maximus fucked with his head, I hate the Inhumans so much), of course, but the writer does put it in there.
And this wasn't Maximus. There is yet another psychic who thinks Pietro's mind is his to mess with so he can achieve his own goals--really, why have we not had a story where someone addresses that psychics (Professor X, Moondragon, Maximus, and now this Videmus dude) don't seem to care about Quicksilver's sanity or rights? Is it the high-speed brain, does it come off as a buzzing that annoys them and they have to stick their hands in there and stop it? Marvel needs an alternate universe where there are no telepaths and as a result all of Magneto's children (and a number of other characters) are in fine mental health. And Magneto needs to see it so he can stop taking his kids to Charles Xavier rather than real therapy.
*Ahem* Back to the original subject, Secret Invasion also establishes a Skrull presence in Attilan. As a result, I look at this and see even more people manipulating Quicksilver in addition to the rogue telepath he connected minds with, the brain moving too fast thing, the depression, the trauma of having been killed by his own father and been brought back to life by a woman with the power to make things go horribly wrong, and then the mental stress of either having a witch use him as a power familiar to focus a spell that changed reality/history and then one that changed the whole multiverse or having to help mentally guild an ultra-powerful reality warping emotionally unbalanced mutant in creating a coherent reality. (Oh, did I mention that I think the Scarlet Witch basically used him as her cat when she cast the House of M and M-Day spells? Well... more on that in the "Ways a clever writer could save Wanda" post I'll probably get to before the next issue of Children's Crusade.)
So that takes care of everything from M-Day to the to the Terrigen Mists. He was losing his sanity and getting desperate, so he tries what he can to get his powers back. What he can try is to expose himself to a dangerous chemical that warps his physical body, has undocumented effects on the human/mutant mind, does nothing to solve his problem of his brain moving faster than his body, and triggers a power that has an even greater detriment to his sanity: Time Travel. Pietro's very first use of time travel is to meet his horrible future self, a future self who tricks him into murdering someone and exposing himself to that drug more. From this point on, he takes it more and more and gets worse and worse until he gets thrown into detox for the Quick and the Dead, goes through withdrawal and his natural powers come back completely. It's pretty obvious that all of his actions from that point onwards were to be attributed to the Mists. I'd argue that the actions leading up to it can be excused as temporary insanity, too, because of the trauma in House of M #7 and the disconnect between his perceptions and his actions.
This brings us to House of M. Nothing can save the character from that, right? Well... Maybe Magneto can.
In House of M #1 Magneto finds Pietro at his sister's bedside and demands to know why he's there. That little question is glossed over but it is the oddest thing for Magneto to say. This is Quicksilver of Quicksilver and the Scarlet Witch here. Also known as Pietro "Is my sister going to be alright?" Maximoff. Now, I didn't read Excalibur but if Wanda is ill, why wouldn't he be there? We know as teenagers she used to get sick when she used her powers too much, and he used to take care of her during that. He's been playing nursemaid for her at least since they were 13. The thing to question here is that he hasn't been at her side constantly, rearranging the bedding, bringing her water and chicken soup, reading to her, doing anything that can possibly be done to care for a sick person. The only explanation for that question is that Magneto's already made it clear that he's not supposed to be there, probably to prevent Wanda from accidentally hurting him.
But Pietro's in the room in House of M #1, and this can't be the first time he's been there. And maybe... it's not the first time Pietro's tried to help Wanda control that power. I mean, it wouldn't be the first time he's applied his will to a mystical situation to try and help her (see "Nights of Wundagore", which is either magic or a result of Wanda's power by the Bendis retcon so it applies either way) and they probably couldn't have created a world so intense without having practiced first. Maybe whatever caused Wanda to lose her sanity got passed onto Pietro and amped up the stress level, leading to his own actions in that miniseries. If they go by that hateful idea that those powers cost Wanda her sanity, can you imagine what they did to the guy who's not built to have them? If it's just magic getting out of hand it makes even more sense that he was affected. And if she's being possessed or affected by some external source then that's probably been passed on to him by the opening of the miniseries too.
My point is, for a clever writer (or even just one with eyes) there's no reason to completely retcon out the past few years to save Quicksilver as a heroic character. His actions in Son of M were terrible, but there was major external interference causing it. Any combination of the items I mentioned above could be explored in a scene where someone questions Quicksilver's return to the Avengers and you can use him cleanly afterwards.
Crystal, on the other hand, would benefit greatly from all of us forgetting this miniseries ever happened.