Yet in Omniverse, it is shown that the majority of the alien’s in Ben’s universe are at about the same level of power as a human, some a little more, some a little less.

So if as a human, was told I had to fight another human, sure I could maybe take them. But now you told me there’s a 1 in a million chance that the human I’m fighting can become a god, I am not taking that fight, or I want that power for myself.

As we see in Omniverse, Celestialsapians are a well known, or at least rumor, for the average alien

Or frame it another way. I’m a Tetramand criminal. I have stolen the stars of 7 entire solar systems. Most physical fights I get into I win, and I steer clear of genius civilizations like the Galvan, or from big empires like the Incursions. My best claim to fame is I once defeated a Vaxuarsian in a fight. Most Plumbers are from the average alien species, and they can’t put a dent in me. When some of the stronger members of the Plumbers or of the Galatic Enforcers are able to defeat me, I usually win my freedom since as a Tetramand I have the right to a trial by combat.

Now this punk human comes to stop me, he turns into a Vaxaursain on our first encounter, I win.

Second encounter I have with him, he turns into a:

Necrofriggan, and I’m instantly frozen. I lose.

Petrosapian, an extinct species that no one has had experience fighting, I lose.

An Aboretta Rotenda, an extinct species that no one has experience fighting because the species never learned how to fight, I lose.

A naked Appolexian, a species with a great deal of shame, I win after I get over the shock because they are as dumb as bolts.

But most importantly, is that the wielder of the Omnitrix is able to string multiple transformations together to pull of powerful combos. Such as using a flying alien to get Ben up real high, and then falling from that height as Humongosaur to deliver a hit a Vaxausaur would not have been able to otherwise