In the Marvel Universe, most aliens appear to be about human level in power. A few might be a bit stronger like the Shi'ar. If a race is "superpowered" generally the entire race shares that power: Skrulls, Stronians, Majedians, Kronans, Watchers, etc. Advanced races can give superpowers or use technology to simulate super-powers, but this appears rare. The Skrulls only recently got around to creating Super-Skrulls in mass. The Shi'ar is composed of who knows how many sentients and can use technology to duplicate or give superpowers. The Imperial Guard has types or clashes with the elite of the Guard being the best of each class. But the average Shi'ar soldier is armed with a blaster or blades. It seems it is difficult to give beings superpowers.
On a whole Marvel Earth is different. Virtually anyone can get superpowers from anything. Things that all rights would kill an alien humans can somehow survive. The diversity of the powers is unheard of. And as noted by several characters that is not all. The sorcerer supreme makes him home on Earth. Galactus was repealed. Earth survived the judgement of the Celestials. Humans have developed technology that other races have taken far longer to achieve. Mutants are born with powers that the cosmic beings achieved over millions of years.
What are all the reason in-universe writers have given for Earth being special? I can remember a few. Are there any others? Anybody have anything to add on those I have listed?
1. The Celestials created Eternals, Deviants, and mutants.
The Celestials gave primitive humans the capability for benevolent mutations. Apparently, they have done this to other worlds, but Earth is the first one to successfully develop or at least not destroy itself yet. Is this story still canon?
2. The Universal Wellsprings:
IIRC, this was the story where the Thunderbolts under Zemo battled the Grandmaster. Apparently, Earth sits on some sort of magical/cosmic source of energy. This energy leaks out around Earth and breaks down the laws of physics allowing the impossible to otherwise become possible. That is why a random burst of radiation that should kill a human lets them survive. It may also explain why certain technological developments are possible.
3. Dimensional travel is easier on and around Earth.
For whatever reason, it is easier to travel between dimensions, alternate realities, and time on Earth then in other parts of the universe. That would help explain why Earth is the focus of extra-dimensional attacks, alternate reality invasions, and time travel is so easy. It would also help explain why so many superpowered beings are connected to extra dimensional sources of power.
4. The Death Celestial
Someone is going to have to feel me in on the details because I only briefly read part of this one. I think it was from Fraction's recent run on the Defenders. If I understand it, something called the Death Celestial was imprisoned on Earth, awakening on Earth, something. To counter it the Celestials put machines on Earth (are they called anything specific?) to bring together special beings across the multiverse all to one place to help fight it. Would someone please fill me in on the details of this?
Any others I missed?
By the way, can someone please update me on the Celestials:
1. Once upon a time they were considered at the least equal to Galactus if not far higher than him. Would you say this is still true?
2. Are they still quasi-omnipotent, planet bowing, reality altering giants or only dumb pieces of armor that can shoot energy blasts?
3. I glanced through an X-Men tpb and it had I think a future Wolverine be a monster. That Wolverine justified his actions by stating it was necessary to satisfy the Celestials. The Celestials are actively monitoring Earth and want it to continue evolving. If mutants do not continue to appear as a sign of evolution the Celestials will return and destroy the Earth. Apocalypse is an active agent of theirs who forces conflict to continue evolution. Is this true? Can anyone please elaborate?
4. The recent time travel Thunderbolts story. When they were going back in time they encountered the Celestials. Did the story suggest that the Celestials created the planet Earth itself? What were the Celestials doing?
5. Is it true in a recent Avengers issue a 2,000 ft tall Celestial was killed by Thor's ax? Was it truly killed or was it faking it? Why is Kang at war with the Celestials?
6. Is it true that Mr. Sinsiter "hacked" into the Dreaming Celestial like it was some sort of robot? Then the rest came, but just decided to leave a suddenly?
7. Did SHIELD as run by Da Vinci encounter the Celestials? Did they really somehow turn them back? If so, HOW?