|Dr. Henry Killinger|
|1st appearance:||I Know Why the Caged Bird Kills|
|Voice Artist:||Christopher McCulloch|
First appearance falling arches Dr. Henry Killinger is a mysterious figure dressed in a black doctor's uniform and accompanied by a medical bag that he affectionately calls his "Magic Murder Bag". Killinger's Modus Operandi is to show up out of the sky and use his uncanny organizational skills to help others. His motivations remain suspiciously ambiguous.
The doctor first appeared to help The Monarch whip the Horde into shape. He was shown to be very insightful and quickly became The Monarch's second in command. By the end he had brought Dr. Girlfriend and The Monarch back together.
He later married The Monarch and Dr. Girlfriend, wished them the best of luck, and fled the wedding in order to escape the assault Phantom Limb had organized.
By using an Oni demon, who seems to be in his employ, he attempted to reunite Dr. Venture with former bodyguard Myra Brandish. Though he failed in this task, he took comfort in the fact that the Oni's actions saved Hank and Dean's lives.
Dr. Killinger later came to Dr. Venture's aide and helped make Venture Industries once again into a booming business. The only catch was that in order to do so Rusty had unknowingly become a villain.
Dr. Killinger was later shown to be a new recruit of the Revenge Society.
- Killinger is an obvious likeness and reference to the famed Dr. Henry Kissinger, the Secretary of State and National Security Advisor during the Nixon and Ford administrations.
- Mary Poppins, including his carpet bag and umbrella as well as his sudden appearance and ability to bring everybody together.
- Dr. Henry Killinger is also looked at as the devil from the episode The Doctor is Sin. He interprets acts of the Bible and acts as the devil in these metaphors. As Dr. Orpheus says, "his is the way of the serpent and the apple." Killinger, when giving Dr. Venture his new supervillain costume, also claims to have given Richard Nixon his first power tie. His strange and awesome powers appear to be beyond any others in the show.
 Episode Appearances
- I Know Why the Caged Bird Kills
- Showdown at Cremation Creek (Part 1)
- Showdown at Cremation Creek (Part 2)
- The Doctor is Sin
- Bot Seeks Bot