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Project Caliban, also referred to as the Protomolecule project, was an attempt by Mao-Kwikowski Mercantile to create human super soldiers. The project was ultimately backed by the Martian government as means of asserting their dominance over their stronger rival, the United Nations. The project was, however, uncovered by Chrisjen Avasarala, and the MCR lost their partnership with Jules-Pierre Mao after the death of Defense Minister Pyotr Korshunov. UN Undersecretary Sadavir Errinwright renewed his alliance with Mao for the good of the United Nations, with the former allowing the continuation of the project.

History Edit

Bobbie holding data plaque on Project Caliban

Also known as the "Mao protomolecule hybrid", this creature was an attempt by Mao-Kwikowski Mercantile to create human super soldiers.

The Hybrid was first tested on Ganymede, where it successfully defeated a group of UN soldiers along with most of Bobbie Draper's squadron. Draper would later defect to the UN as a result, furious with her government's involvement in the attack and determined to learn more about the creature's origin. Eventually, thanks to a redirected grenade from Amos Burton, the Hybrid broke out of its cage on Ganymede station, slaughtered the scientists and guards in its holding area and escaped through the nearby airlock, fleeing across the surface of Ganymede. James Holden, Alex Kamal and Praxideke Meng pursued it in the Rocinante, but were forced to abandon their hunt in order to help the refugees aboard the Weeping Somnambulist. Shortly after, however, the Hybrid managed to attach itself to the Rocinante during its pursuit and broke into the ship's cargo bay. Once it removed and discarded the explosive device in its chest, Holden and Amos opened fire, but the Hybrid shrugged off its wounds and hurled a cargo container at Holden, pinning him to the wall. No longer considering them a threat, the Hybrid began punching a hole in the floor, attempting to reach the Roci's nuclear reactor. Alex shut off the Epstein drive to prevent this from happening, but the Hybrid began to take an interest in Holden as a consequence, forcing Alex to reactivate the ship's engine. Fortunately, Praxideke suggested luring it off the ship using an alternative energy source: a nuclear warhead from one of the Rocinante's missiles. Despite Prax's hesitation that the Hybrid might be his daughter, the plan worked, and Alex ultimately destroyed it with the Roci's afterburner.

Physical AppearanceEdit

The hybrids are roughly humanoid, but the head is about twice as large as a human head and covered in protruding growths, and their hands are large and long. The skin is covered in black, chitinous scales, and the eyes glow with a bright blue light.

Powers and AbilitiesEdit

Frozen protomolecule-infected child

Frozen infected child

By infecting humans without immune systems (such as children with Myers-Skelton Premature Immunosenescence), Mao-Kwikowski attempted to control the infection and reshape the hosts into weapons. The result was a powerful and durable entity that could survive in hard vacuum, move at great speeds, cling to any surface, and tear through hull plating and armored targets with its bare hands. When left to their own devices, the hybrids were attracted to and would chase after energy sources, such as radiation, to feed on them.

Hybrid as seen by Bobbie on Ganymede

Close-up of a hybrid as seen by Bobbie Draper.

Although they successfully created an army of such hybrids in their research labs on the Jovian moon Io, they were unable to completely implement constraints for the protomolecule. As a failsafe, bombs were implanted in the hybrids' torsos, rigged to explode if the host was altered significantly after deployment. However, the oldest hybrids were eventually able to adapt to these bombs, expelling them from their bodies without setting them off, leaving them completely uncontrollable.


  • In the books, the project is not given an explicit name however the MCRN referred to it as the 'Anomaly'.


  • The project takes its name from Caliban, a villainous and deformed character in William Shakespeare's The Tempest.
    • Similar to Mao-Kwikowski, Caliban also had plans to create more versions of himself, but was ultimately thwarted.

Media Edit