Warning: contains spoilers to Doctor Strange in the Multiverse of Madness!Since the film's release in May, fans and critics of Doctor Strange in the Multiverse of Madness have debated over whether Scarlet Witch should have been able to defeat Reed Richards as easily as she does. After all, wouldn't the "smartest man alive" be able to defend himself better against Wanda Maximoff and her Chaos Magic? According to Mr. Fantastic himself, no he would not.
In Multiverse of Madness, Wanda's magic causes Reed's demise. In the film, the Wanda of the MCU's main Earth "dreamwalks" into her Earth-838 counterpart, taking control of her parallel self as she hunts for Doctor Strange and America Chavez. Here, she confronts the Illuminati, Earth-838's clandestine group of superhero leaders and defenders. After Earth-838's Reed Richards, an Illuminati member, tells Wanda that Black Bolt can kill her with a word, the Scarlet Witch murders Black Bolt before killing Mr. Fantastic himself, shredding the elastic man to death.
James Robinson and Marc Laming's Fantastic Four #10 sees Reed take on a new version of the Frightful Four, led by the Wizard. The other three members - Reptilla, Gazelle and Vertigo - are all female members of Salem's Seven, a group of seven magic users who are grandchildren of Scarlet Witch's friend and mentor, Agatha Harkness. While fighting the new Frightful Four, Reed admits his scientific ability leaves him out of his element in fights against magic, with no real way to combat forces beyond his understanding: "Magic... chaotic energy ungoverned by natural laws... and me, a man of science. Magic and I... we don't get along." Eventually, the Scarlet Witch herself saves Reed, who surely would've perished on his own against his magical foes, admitting, "Magic has always been difficult for me, even on my better days."
Reed Richards Can't Fight Magic
Reed's hatred of magic helps explain why he went out so quickly in Multiverse of Madness. Despite knowing everything there is to know about the natural world, he feels completely in the dark against powers like the Scarlet Witch's. In some cases of Marvel canon, Reed outright refuses to believe magical acts from beings like Doctor Strange and Doctor Doom, trying to explain them away as unexplored fields of science. Reed isn't just as vulnerable to magic as a normal person - he's particularly unable to predict and work against is, since he always expects the world to follow the laws of science. Even at his best, it's easy to surprise Reed with a magical attack, since his enormous scientific intellect leads him to constantly underestimate mystical assaults.
Mister Fantastic Won't Even Admit Magic Exists
Even as one of the Marvel universe's greatest minds, Mr. Fantastic has always been hopelessly outmatched against magic. This, in part, is what makes Doctor Doom such a powerful adversary for him. Reed Richards often follows a personal mission to "solve everything," but magical foes like Scarlet Witch prove scientifically unsolvable - in Doctor Strange in the Multiverse of Madness, that tragically led to his death.