Thanos is an
The explanation for why the Eternals couldn't help fight Thanos makes no sense. In the Eternals movie, Sersi said that the Eternals couldn't fight Thanos because they could only fight in conflicts that involved Deviants. However, letting Thanos win directly affects the Celestials' grand plan.
Eros turned out to be 100 % Eternal, but Thanos did not. As soon as he was born, Thanos' mother noticed that he had Deviant genes and actually tried to kill him. Thanos was born with purple skin and pitch-black eyes, and his general physique was so much different than what they would have expected.
Due to this strange mutation in Thanos's DNA, Thanos has heightened abilities and bears some physical similarities to the Deviants (but is still an Eternal). It's possible there are other Eternals in the Marvel Universe who have the Deviant Syndrome, but Thanos is the only character confirmed to possess it.
Unlike the Deviants, the Eternals' human-like appearance has allowed them to seamlessly live among humanity. However, the Eternals' superhuman gifts have sometimes caused them to be mistaken as gods, much to the annoyance of actual deities like Zeus and the Greek pantheon.
Film. Kro serves as the secondary antagonist in the Marvel Cinematic Universe film Eternals (2021), voiced by Bill Skarsgård. He is a Deviant general and an enemy of the Eternals. By assassinating Ajak and absorbing her powers, Kro and the Deviants begin to evolve.
While still an intellectually superior race capable of advanced genetic engineering, the Deviants in Marvel Comics are said to primarily hold inferior powers to the Eternals, placing Thanos at least two rungs above them in the cosmic pecking order.
Thanos was born on Saturn's moon Titan as the son of Eternals A'lars and Sui-San, the grandson of Kronos, the nephew of Zuras, and the grandnephew of Oceanus and Uranos. His brother is Eros of Titan. Thanos carries the Deviants gene, and as such, shares the physical appearance of the Eternals' cousin race.
In the comics, Thanos and Eros are born on the Saturnian moon Titan to two Eternal parents, A'lars and Sui-San. Eros is born without the Deviant mutation, but Thanos is born with Deviant Syndrome. They're biological brothers, but they look wildly different. So, in the original comics, Thanos is an Eternal, full stop.
Quill becomes the leader of the Guardians of the Galaxy after they assemble out of necessity to stop Ronan the Accuser from destroying Xandar. He discovers that he is a Celestial hybrid and that his father, Ego, created him as a means to terraform planets.
ErosStarfox. Eros grew up on Titan alongside his brother Thanos, embracing all the pleasures that life has to offer. He laters becomes Starfox and an official member of the Avengers.
Where Eros serves as the superhero Starfox, he is opposed by his mad brother Thanos, much like the rest of the universe. He has the power to psychically control other people's emotions. He was a member of the Avengers and Dark Guardians.
Created by Jim Starlin and first appearing in 1973's Invincible Iron Man #55, Eros is Thanos' younger brother. With good looks and the power to influence other people's emotions, Eros is both the superhero called Starfox and a massive fuckboi.
The Eternals were instructed not to interfere with any human conflict unless Deviants are involved. There's a reason why that's the case. And that was the instruction from the prime Celestial Arishem.”
At the end of Eternals we see Arishem come to Earth to take the Eternals away you can see that his mere size causes disruptions to the atmosphere. We know that the birth of Tiamut was causing global earthquakes.
Shortly after Starfox joined the team, the first encounter between the Avengers and the Eternals unfolded in AVENGERS (1963) #246-248.
It has been shown in the comics that Starfox has the speed and strength to deal with Thanos' blows. However, he usually crumbles under the weight of the villain's physical might after a while. Because of the events of Endgame, there will be no need for Starfox to oppose his brother in any future MCU films.
In the comics, Thena was born Azura, but her name was changed to resemble more the Greek goddess of Strategy and War, Athena. She mothered a son, Joey, with a human, Thomas Eliot. She is also the daughter of Zuras, and cousin of Thanos.
Thanos is not a robot. Nothing can or will ever change that.
Galactus is not a Celestial. Both are considered space gods threatening to destroy the earth. Both are giants with unimaginable power and have very similar wardrobes in the comics. Although they have almost identical identities, appearances, and goals, they have a huge difference that sets them apart.