Marvel may have secretly revealed the Eternals' power source. The Marvel Cinematic Universe is expanding at a prodigious rate, introducing increasingly powerful heroes into the mix. No sooner does Marvel announce that one superhero is their most powerful than they wind up superseded by the next, with Scarlet Witch currently the strongest Marvel hero. But it's a rank Wanda Maximoff is unlikely to hold for long, because the next Marvel blockbuster will introduce a race of ancient aliens who are literally the inspiration for many of the legends of Greek gods and heroes.

Each of the Eternals possesses a distinctive power. Ikaris is a physical powerhouse who can project cosmic energy from his eyes; Sersi can manipulate matter at an atomic level; Ajak is a healer who can communicate directly with the Celestials; Phastos is an inventor who can create anything he can imagine; Makkari is a super-speedster who has weaponized her sonic boom; Gilgamesh projects an exoskeleton composed of cosmic energy; Thena can form any weapon she can imagine; Kingo projects projectiles composed of cosmic energy; and Spire is an illusionist. The common denominator appears to be the manipulation of cosmic energy, but the interesting question is just how the Eternals came to possess these powers.

Related: Marvel's Eternals Powers Explained: What Each Team Member Can Do

In the comics, the Eternals are an evolutionary offshoot of humanity created by a race of cosmic beings called the Celestials. The MCU has reinvented their origin, however, revealing they are actually ancient aliens who were sent to Earth by the Celestials in order to protect the Earth from another race called the Deviants. One intriguing scene in the final Eternals trailer may well show their being empowered by the Celestials; they are shown gathered around a statue of a Celestial, before glowing light emerges from it and is shown entering into one of the Eternals, Ajak.

This "living light" is something viewers have seen before, in Guardians of the Galaxy Vol. 2. There, the Guardians of the Galaxy confronted Ego, who believed himself to be the last of the Celestials. The center of Ego's planet contained a shimmering lattice of light, the core of Ego's being, and the Guardians killed him by destroying it. It's possible the final Eternals trailer shows the Celestials empowering the Eternals by sharing a fragment of their own cosmic energy with them; that would explain how the Eternals came to be so powerful, and why those abilities do not diminish with age. It would further underscore the importance of the Eternals, because until now there hasn't been a hint the Celestials were willing to share their powers.

If this is indeed the case, then it raises a lot more curious questions - the most notable being why the Earth is so important to the Celestials. In the comics, the Celestials traveled the galaxy manipulating evolution and judging the fruit of their labors, and the same may well be the case in the MCU as well, with the Deviants somehow a threat to their plans for humanity. Alternatively, the Eternals may have been positioned on Earth to ensure this mysterious "Emergence" really does take place, in spite of Deviant opposition. The truth will likely only be revealed when Marvel's Eternals movie comes out in cinemas.

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