Who defeated Iron Legacy?

I was thinking about this. We've (generally) deduced who was present to defeat various of the villains in the lore. Do we know who took down Iron Legacy?

Legacy and Young Legacy were involved at the least because that is what prevents either of them from getting hit by Blade's regression darts and getting killed.  

I think pretty much everyone who shows up on his art was there to defeat him.

There were two waves of heroes (I assume from both universes).

“We’ve (generally) deduced who was present to defeat various of the villains in the lore.”

Care to expand?

By the art of the cards -- Oblivion has Nightmist sealing Voss in a rift and banishing him, so it's generally agreed she was there to defeat him (at least on one occasion).