Gearing up for its major upcoming crossover, Judgment Day, billed as a war between the Eternals, the Avengers and the X-Men, Marvel has released a trio of teasers. In doing so, the company suggested the Eternals will soon be looking at mutants in an entirely different way, as essentially Deviants.
The whole origin of the Eternals (and Marvel's Earth, period), is that the Celestials came to Earth millennia ago and experimented on the being that they found, with some of them being transformed into Eternals, some being transformed into Deviants and the rest becoming humanity. However, a back-up story in an issue of What If...? in 1980 revealed that the Celestials left a little something extra in humanity. X-Men Annual #13 confirmed that "little something" was, in fact, the X-Gene.
The X-Gene, of course, later led to the introduction of mutants on Earth, but that was never seen to be a problem between mutants and Eternals. The X-Men have had a number of interactions with the Eternals without issue, even though one of the Eternals, Phastos, accidentally nearly doomed all of humanity when he took pity on some Neanderthals that he knew would soon be extinct, giving them technology meant to protect evolution on Earth. Phastos meant humanity, but that soon meant mutants -- and these Neanderthals almost took that protection to absurd degrees.
Now, however, the Eternals appear to be lumping mutants in with the Eternals' lifelong enemies, the Deviants, under the understanding that if mutants aren't Eternals and they aren't quite humans, then they must be Deviants by default. That scary reimagining of the mutants placed alongside the Eternals will likely be the driving force of this upcoming war.
The other two teasers are a bit less shocking, although they are intriguing in their own regard. The Avengers teaser suggests the Avengers might have to create their own Eternal to match up in this upcoming war.
The X-Men teaser is merely Irene "Destiny" Adler suggesting that war is definitely coming, which means a lot coming from her, considering she has the power of precognition. As more of Marvel's plans for May 2022 are released, more of the Judgment Day setup will be exposed.
Source: Marvel