Thena’s Mahd W’yry Illness In Eternals Explained – /Film

In comic lore, Eternals (first appearance in "Eternals" #1, July 1976) aren't created by Celestials ex nihilo, but rather are the product of Celestials' experimentations on humanity. They emerged a million years ago when Celestials arrived on Earth and experimented on early humanity to produce both the Eternals and the Deviants, the latter possessing power alongside genetic instability. Eternals areimbued with cosmic energy, resultingin a vast array of unique powers like superhuman strength, flight, the ability to create force blasts, illusions, weaponized energy, to transmute matter and energy if it's powerful and can be done, it's a possible Eternal power. In addition to their ordinary longevity, Eternals can be restored to life upon destruction and essentially regenerated via "the Machine", the Celestial technology that creates the Eternals. Each group of eternals has a Prime Eternal whose powers can be enhanced by the collective creating a Uni-Mind, in essence a psychic meta-Eternal entity that has the powers of all the Eternals creating it.

With all these immense powers, they're subject to the aforementioned unique condition mahd wy'ry as a consequence of their immortality. (Yes, the burden of memory makes them mad and weary, and yes "mad weary" is how the condition is pronounced).In the comics, mahd w'yry is explained as a Celestial mistake (in "Avengers" #361), the product of imbuing human bodies with vast cosmic powers that last over millennia but with human minds and consciousnesses. It reportedly takes centuries to set in once it starts (though it can set in sooner) as the collective weight of experiences and memories take a toll on the Eternals' essentially human minds. The affliction can possibly be held at bay via the Eternals' abilities to share consciousness via the Uni-Mind or via their chosen life mate (in a process called "Gann Josin"), but as Ikaris explains in #361, the primary known cure isis an ancient "rite of cleansing"... the "molecular discorporation" of the increasingly mad Eternal. In effect, the afflicted Eternal's aforementioned death followed by their reconstruction via said "Machine."

Unlike the film, Thena isn't an eternal that suffers from the illness in comic lore. In the aforementioned issue #361, it's Sersi who suffers the disorder and faces destruction and reconstitution (which they ultimately don't do). It's also possible Sprite was affected by the disorder, provoking the idea to use the Dreaming Celestial to turn Sprite human and allow normal aging (instead of Sprite's perpetual childhood visage). It can hypothetically affect any Eternal, however, and the standard solution is a hard reboot of the afflicted Eternal.

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Thena's Mahd W'yry Illness In Eternals Explained - /Film