It's dark, the crappy neighborhood lit only by the sparse streetlights and the occasional lit window. There are twenty or so gang members in ABB colors, red and green, clustered around the tall, muscled asian man in the dragon mask and covered in elaborate tattoos - Lung. According to Parahumans Online, he has the ability to grow stronger, faster, and tougher the longer he's in a fight, growing scales and claws, and also create and control fire. He's fought off the protectorate more than once, and rumors say he even took on Leviathan one on one and lived. Not someone you want to run into so early into your cape career, to be honest.

You're on a neighboring rooftop, out of sight, and creep closer to get a better look. Finally, you get close enough to hear Lung snarl, “…the children, just shoot. Doesn’t matter your aim, just shoot. You see one lying on the ground? Shoot the little bitch twice more to be sure. We give them no chances to be clever or lucky, understand?”

There is a murmur of assent.

Someone lights up a cigarette, and then leans over to light a cigarette for the guy next to him. In the brief flare of light, you see the gathered faces of just a dozen or so of the gangsters gathered around Lung. In hands, waistbands and holsters, you see the dark metal of guns reflecting the orange flame.

Who are you, what are your powers, and what do you do now?

Story takes place in Worm universe (and select text is copied, all rights go to Wildbow), but knowledge of setting is not required and will be provided as needed. You don't have to be a hero, but even villains know better than to openly attack children, lest they draw heat from capes on both sides of the law. There are some unwritten rules, after all. Just to forestall the inevitable "I go along and gleefully murder children" posts. You're also probably not in his gang if you're not asian.

Here is the wiki on power classifications for examples.