Granted it's a cameo appearance, but he's seen in 'The Bar With No Name' having a drink with none other than Count Nefaria. Questions arise... what's he drinking?... It doesn't look like blood, and why's he gripping Neraria's arm?
Now there's a thought... Baron Blood, and Count Nefaria in their own super-villain team, a sort of masters of evil type of thing. Who would be good additions to their group?