He makes things explode. As well as having boosted stats (strength and toughness in the class 25 range or so, high reflexes and speed, etc.).
Grant was the son of the original JSA Atom (the one with strength, not one of the shrinkers) with the DNA of a buncha other heroes spliced into him. In short, he was made to be a super super, with whole tons of power that could hypothetically be used for lots of purposes, but mostly lacks the ability to use it for more than basic ones, with 'explosion' being the easiest of all.
Sebastian has no equals in DC (basically no copies). Written to his full potential, Sebastian should be unstoppable and he knows this, that's why he has the cocky attitude he has. Everyone should be treated like he treated classic Rogue on the Xmen cartoon when they fought each other.
The sad thing is, he doesn't show this potential in comics.
There are people out there who can overload him in a relatively short time if written correctly. You can't honestly think Shaw can just amp to fight anyone.
Possibly could. What's his limits? Who has overloaded him? I heard Magneto did but what did Magneto do to over load him and if that was the case, it could have been more of a low showing for Sebastian.
He has no established limits. But lots of characters don't have limits on paper, but very clearly do in the comics. And Magneto overloaded him by dropping barrels on him.
I don't read Shaw much, but to say that he can amp fast enough without overloading to fight people who would obviously demolish him...I think it's called a no-limits fallacy or something.
I don't think he can beat "everyone" but being capable of absorbing kinetic energy is one of the best physical powers to have... he "should" be unstoppable.
See, he has no established limits, but it's clear he can be overloaded. By something as mundane as barrels dropping on his head. On the other hand, you've got this guy http://marvel.wikia.com/Maelstrom who is at a level Shaw isn't even allowed to dream about.
He was taking full on punches from Thor with no problems.
I figure a punch or two from Thor would overload Sebastian.
You can't apply a no limits thing to him just because he hasn't had one stated. He's been beaten by people who could get around his powers, so it's not like he's going to be a herald buster any time soon.