Well, I've been looking through most of the cards in the game, and I can't find any other appearances of this red-eyed figure. I don't know how much faith I have in this theory.
Ok… reading through the new cards a little last night, and one of Argent Adept's cards has a quote from someone called "Siege-Breaker" (or "Buster"… something Siege-y). If that's not the name of Bunker's nemesis then it should be.
I hope so. That's an awesome name.
Seige-Breaker is an excellent name for Bunker's nemesis. The guy on the card (Polyphoric Flare, if I'm not mistaken) looks like he's wearing some sort of suit, which makes sense. However, if the guy on the card is this Seige-Breaker, he doesn't quite have that villainous edge to his appearance. Maybe a lieutenant or something, though. (No offense if that's somebody's picture. 
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