Oh man, I was rereading the Fiendish Codexs in case I missed something since Bambu pointed out things he found and there's this statement.
THE LORD OF NESSUS
Asmodeus appears as a horned, red-skinned humanoid with a tall, lithe frame. He dresses in splendid robes and understated but elegant accouterments. Half-healed wounds erupt from his skin like the canyons that scar the Nessian landscape. These injuries are the result of an incident not usually recounted in the creation story.
In fact, Asmodeus's parting from the lawful deities after the signing of the Pact Primeval was not amicable. Once he had committed himself to residing in Baator, the deities physically cast him out of the upper realms, and he fell—and fell, and fell. Upon reaching the plain of Baator, he plunged through the nascent layers he had begun to shape. (In some versions, his fall created the layers, breaking the formerly featureless plain into nine pieces, which then arranged themselves into floating tiers.)
At last he hit solid ground but continued to fall, spiraling through rock and soil. The protesting earth of Baator tore at his flesh, opening scores of gaping wounds. Still he fell, until he could fall no farther. The point where he finally stopped was the deepest part of Baator—the Pit. The wounds that Asmodeus suffered in his dramatic fall have never healed. Though he manages to appear blithely unperturbed by his injuries, they still weep blood every day, and he has been wracked by constant pain for millennia.
As the unquestioned master of Baator, Asmodeus can work nearly any magic within its boundaries as an act of will. He can alter the forms of other archdukes, though he might not be able to slay them outright. (Whether the demise of Malagarde the Hag Countess was the direct work of Asmodeus or simply a bizarre death remains an unanswered question.) He can also reach into other realms and reshape them with the merest thought.
Souce: Fiendish Codex II: Tyrants of the Nine Hells pg. 73
Now this does sound like a solid 2-C feat, however, this is 3e and the Nine Hells were not infinite in that edition.
However they were still huge afmeaning he at least shattered like 10,000 miles of rock when he was judo tossed to Baator.