- "A simple compound of one part Brennenburg Infusion Vitae to one part Orgone Monad Disperal fluid is sufficient. This can then be administered intravenously to subjects following re-assembly to maintain bonding. The compound is unstable and highly light reactive - once in the body, the Schumann Lamp can be used to activate the compound, but outside the body is highly corrosive. It can even destroy small quantities of metal. "
- -Oswald's Documents, July 15th, 1899
Compound X is a liquid created from a mixture of Brennenburg Infusion Vitae and Orgone Monad Disperal fluid. It is used to facilitate bonding between Human and Pig cells in order to successfully create the deformed and sewn-together Manpigs. It is used by Oswald Mandus in a similar way to the poisonous wine from The Dark Descent in Amnesia: A Machine for Pigs.
Compound X is a very dangerous, highly flammable, toxic and corrosive mixture. Because of its unstable nature, it is very reactive to light. When exposed to heavy lighting the liquid will burn fiercely, as can be seen when the player destroys the lock on the gate in the Tunnels level. The compound also has an effect on electrical devices, causing the lantern to flicker heavily when a Manpig is near. This type of interaction is also seen when the player uses the Spark Plug during the Pigline level.
Inside living bodies, Compound X has highly mysterious properties, most notably its ability to bring deceased creatures back to life. Some notes suggest that it can even reanimate formless, raw flesh, which makes disposal of its subjects a difficult task. It appears that in some conditions it can even cause its subjects to uncontrollably flicker between two worlds as well.
- The rods in the rod control room are reminiscent of those in nuclear reactors. When Oswald is near to the exposed Compound X, a sound similar to the Geiger counter can be heard; this seems to imply that Compound X is a radioactive compound.