The Black Flame is the name of a creature seen throughout the Hellboy Universe on several host bodies. Its supernatural powers are connected in some way to the Ogdru Hem creatures.
Raimund Diestel (The 1930s Black Flame)
Raimund Diestel as the Black Flame
The first known Black Flame was Raimund Diestel. He and his wife, a Siamese woman called Kamala, were mystics hired by mob boss Arnie Wald and his henchman Mr. Isog. (see: The Burning Hand)
In the early part of The Burning Hand, he appeared in a long coat and a hat that concealed his face. Later he is revealed as a skeleton engulfed in black flame.
The Lobster first confronted The Black Flame in early 1932 when he was burning down some tenements for Wald. In the fight that followed, the Black Flame is shown to be unaffected by bullets, as there is no flesh to damage. One of the Lobster's crew, Massimo, was burnt, killed and his body abducted by the Black Flame.
With Massimo's body, Kamala conducted an occult ritual to absorb his knowledge of the Lobster. With this, Wald, his goons and The Black Flame launch a raid on the Lobster's warehouse headquarters. The Black Flame is seemingly unstoppable until the Lobster uncovers a cannon and blasts him with a high-caliber shell.
For a moment the Black Flame appears defeated, but Kamala begins to sing, and the flames reignite. The confrontation ends when a car rams into Kamala, killing her. The Black Flame immediately rushes to her side, utters, "Kleine...?" then falls to the ground as his flame diminishes.
He is last seen handcuffed and taken away by the police. Very little is known about Raimund Diestel after this point in time. He was shown in The Dead #3 in a photograph labelled, "Black Flame? Photographed during experimental flight of "Flying Wing". 9/20/44". In The Black Flame, Diestel's remains are shown in Landis Pope's secret office in a glass case.
Raimund Diestel will return in Sledgehammer 44: Lightning War. The synopsis mentions the "Flying Wing" and previews for the first issue confirm this version of the Black Flame to be Raidmund.
Powers and Abilities
The Black Flame is an undead creature, a skeleton wrapped in black flames. These flames are controlled by him and can be summoned into quite a large area around him or onto a specific target. They cannot be extinguished by water and can turn men into burnt skeletons within seconds. The Black Flame is also shown to teleport through a burst of black flame, and is able to take others with him. The Black Flame is German and exclusively speaks that language during his few vocal moments, but can understand English evidently.
Landis Pope (The Black Flame in the Plague of Frogs cycle)
Landis Pope as the Black Flame
During his time as CEO of the Zinco Corporation, Landis Pope acquired the bodily remains of the previous Black Flame, Raimund Diestel, along with several other Nazi artifacts and mystic texts. Under the hidden guidance of the frog monsters, he constructed an armour that allowed him to become the new Black Flame and leader of the frogs. At first he had a blue flame artificially generated by his suit and controlled by the mechanisms on it; immediately after firing Zinco's Board of Directors, Pope completed a ritual with the Frogs, whereupon he burnt with the black spectral flame of his predecessor.
Frogs began to migrate all across North America, heading to Nebraska, called by Pope and his tame frogs to form his army. As the Frog War dragged on, Pope encountered Roger in Raith, Ontario, and wiped out the homonculus and his team. It was at this point the Frogs made Pope's true position clear - his role was simply to light the way for the tired eyes of Katha-Hem, whom the frogs were working to resurrect, and there would be no power for himself. Unable to take off his armour or stop the flame, a horrified Pope suddenly found himself a prisoner within his own army, screaming futilely to the heavens for forgiveness. By the time Katha-Hem was destroyed, he had escaped his jailers, but the respite was brief - he had just enough time to apologize to Liz Sherman for Roger's death before a party of frogs dragged him wailing and despairing down into the bowels of the Earth.
Many months later he was later discovered deep underground, having allied with the King of Fear. The relentless burning of the flame had reduced him to a state much closer to the original Black Flame - the skin and flesh had all been burnt from his head, and the flame now burnt not from the workings of his suit but his own body. This new semi-undead Pope seemed to have embraced his role in the apocalypse. Chatty and gregarious, he treated his surprised BPRD captives with politeness and attentiveness. He proclaimed Abe Sapien to be an evolved form of the frog monsters and went quite far to convince Abe of this - even off-handedly killing the King of Fear to convince Abe that they were allies - but to no avail. He was subsequently killed and his corpse burned to ashes by Liz.
Powers and abilities
Pope had most of the original Black Flame's powers. He apparently lacked the ability to teleport though. In addition to human languages Pope was fluent in many mystic languages, including the languages used by the frogs. Initially his flames were blue-ish black as they were artificially created by ZinCo R&D department, but later as the frogs sing to him, he is engulfed in the real black flame.
Though initially able to remove his armor he gradually bonded with it, thus ending his life as a human. The armor provides substantial protection from harm as well as preventing accidental flame release.
The Black Flame in the Hell on Earth cycle
The Black Flame reborn
The Black Flame's latest incarnation made his debut appearance in The Return of the Master #4. In #5 it is revealed that Zinco was not working to revive Rasputin as Leopold Kurtz and Dr. Kroenen believed, but rather they were trying to revive Landis Pope as the Black Flame. In this they succeeded, with Pope greatly mentally changed by his death and rebirth. Now tied to life, he took control of Zinco and made himself a god over the city of New York, where he was connected to the life of the creatures that lived within it.