- "Geistkraft - the name I have given this new form of energy. It can be conducted through the human nervous systems, activating the most primitive parts of the human cerebellum."
- — Peter Straub
At some point in time, Frederick Barbarossa's powerful sword was created in Thule, being bestowed with the powerful Geistkraft energy. With this energy imbued into the sword, it was discovered that with the energy, it would be able to fully resurrect the Emperor if he was to die. When the Emperor did eventually die, the sword was quickly disassembled, its pieces being scattered across the world in order to prevent the Emperor's resurrection.
Centuries later during World War II, the hilt of Barbarossa's sword was discovered in the salt mines of the mining town of Mittelburg by a team of miners. One of the miners, Klaus Fischer, contacted the Ahnenerbe to come to the town. In the following days, the Ahnenerbe arrived at the town with the objective of securing the hilt for Hitler's personal collection. However, they were unable to remove the hilt from its resting place. With this, the Ahnenerbe contacted Doctor Peter Straub and his scientific team, as well as Gruppenführer Heinz Richter, to come to the town to see what they could do.
While searching for a way to remove the hilt, the Nazis discovered that the hilt was emitting a strange source of energy. Straub then began several experiments to siphon off this energy from the hilt, accidentally discovering what it could do after a cable snapped and killed two guards, reanimating them into zombies. Armed with this knowledge, Straub began to use this energy to create a undead army. Meanwhile, Richter began to use this energy to build new weaponry such as the Tesla Gun. This began to cause conflicts with the two over the purpose of the energy.
Prior to the arrival of the MFAA, Straub was able to have successfully siphoned off enough Geistkraft from the hilt to reanimate the entire Wehrmacht ten times over. Following the MFAA's successful mission in recovering the hilt and destroying both Richter and the Panzermörder, Straub destroyed the town of Mittelburg and collected Richter's head before relocating to his storage facility on Heligoland. There, he would remain there for a few days before an American team of soldiers and the MFAA traveled to the island. While Straub was able to escape with an army of zeppelins, the MFAA were able to recover the Pommel of Barbarossa before destroying the island through a Royal Air Force bombing mission.
Traveling to Berlin by stowing away aboard Straub's zeppelin, the MFAA agents assisted Red Army soldiers in drawing the zeppelin's attention. Straub then proceeded to utilize specialized weapons to turn zombies in Gekochts in an attempt to kill the four MFAA agents. However, the four were able to recover the Blade of Barbarossa from a hidden chamber and proceeded to confront Straub on his zeppelin, where they override his lab, unleashing his zombies. As Straub is brutally murdered by his own creations, the four MFAA agents take their leave after destroying the Stadtjäger. As the four MFAA agents are surrounded, Rideau arrives in a jeep and escapes with the team.
With all three sword pieces, the Bureau of Archaic Technologies began extensive research on all three parts of the sword, experimenting at a research lab in New Mexico. During their research, the Bureau discovered that the sword was forged from a rare ore consisting of magnetic monopoles. These specialized particles were then theorized by Marie to be the conductors of Geistkraft, binding electrons and gravitons together into an entirely new form of energy that defies all modern understandings of quantum mechanics. By resonating the particles at different frequencies, an engineer can split atoms, reverse gravity, and reanimate the dead cells of a mammalian nervous system.
However, the Bureau discovered something frightening within the monopolorized nature of the ore within the sword pieces; instead of a magnetic dipole field emanating from a north pole and circulating around to a south pole as with an ordinary magnet, this remarkable material only acts as a single, isolated north pole. This meant that the Geistkraft energy is limitless, with Marie stating that it may be flowing through Dirac particles from an entirely separate universe, one with different physical laws than the one known to mankind.