Introducing Randy's father, Hrothgar. Much to Randy's embarrassment, Hrothgar is an anti-hero called "Nordic Lightning" (formerly Black Lightning), and strives to put a stop to Professor Blackheart's schemes with his medieval longsword, dirty fighting, an analytical mind and a biting wit.

Unlike Dark McPlaidshirt, Nordic Lightning works under the radar and doesn't seek glory or fame, nor is he out to impress anyone or pull any punches. Professor Blackheart, in fact, doesn't know he exists, despite all the damage he does to his underlings and his plans.
He's also a master of the insult, not unlike Groucho Marx.