You were investigating recent alien activity on Earth. One of the aliens you had attacked had a brain and one eye; this wouldn't be the first time you encountered an alien like that. You were in the sky trying to disable a ship that was shooting a laser below. You were now Humongousuar hanging on the edge, as the laser was heading straight for a hospital. Gwen couldn't help due to her being busy, so you were on your own. And you thought you would never need the Omnitrix again. You then got up as your knee was still sore from crashing into the ground, and you then got an image in your head, causing you to hiss in pain.

You: Wow! What a headache, then again, I did land on my head, so I'm not surprised, but why do I get the feeling someone needed help?

As you got out Super-man, who was flying back to Metropolis, saw the whole thing go down, he checked if you, who was Humongsuar, was alright, but was stunned to see him turning back. He then remembered hearing rumors about the Omnitrix.

Super-man: The Omnitrix does exist.

Timeskip to where I first met Bat-man, Super-man, Flash, Wonder-Woman, Hawkgirl, Martian-Manhunter, and Green-Lantern after battling some aliens.

Hawkgirl: You have the Omnitrix?

Green-Lantern, using his ring against the jets protecting him as Bat-man, who didn't know about the Omnitrix exists was stunned to see someone who could transform into any alien in the galaxy.

You: Wait, you know about the Omnitrix?

Green-Lantern: Of course, kid, it's known all over the galaxy, even the green-lantern corps knows of its existence.

Green-Lantern: Now tell me, kid, how did you get your hands on the Omnitrix?

You: Oh, I found it when I was 10.

All of the heroes, even Bat-man, were stunned that a kid started fighting crime at that age.