I'm just throwing around ideas and I ended up falling on Noxus and Ionia again, specifically Vlad. Now we know he's a part of the black rose, which are usually in the shadows. So it is unlikely he was on the frontlines in the invasion. But could he have been there?
He is never directly connected with the black rose, all we know is that LB's page lists him as an ally. As he is not part of the Noxian military, I doubt he was in Ionia for the invasion. He seems the kind of guy who prefers to stay at home in his castle.
Doubt he was part of it since he doesn't seem to be part of the military.
I totally see him engineering plagues and weapons of biology and black magic to cull the Ionian army. Not a frontliner but a useful weapon nevertheless.
