Golem

Golem, introduced in Fullmetal Alchemist 2: Curse of the Crimson Elixir, are artificially created beings primarily formed from soil. Different types of golems could be made for various applications. The life of a golem could last for just a few hours to several years, but the golem would eventually revert back to ordinary soil. They are a creation of the alchemists of Lebis, originally intended to be used as slaves.

As the primary ingredient for creating one was soil, making a golem's body as black as lead. They also possess a certain level of intelligence, with an ability to grasp basic human speech.

Abilities
Golems range from all different shapes and sizes with each form having its own advantages. Smaller golems have shown the ability to levitate while larger ones are physically stronger.

The larger golems are capable of creating localized tornadoes around their body by spinning. The tornado is capable of thrusting those caught within them back a considerable distance. Some golems are able to create smaller golem's from their own mass. The size of the golems will normally depend on the size of the originating golem. Golems are also able to transform themselves into a human-like form for the purpose of disguising themselves. Though this form does not give them any human-features aside from the appearance, as they can be seen through by their lack of human speech and patterns. A rare ability possessed by some Golems is the ability to project laser beams.

It is possible to use golems as receptacles for soul binding, though this is dangerous due to the instability of the golem body, which will invariably begin to degenerate and mutate before finally collapsing back into mud, an extremely painful process. The physical mutation can be exacerbated with the Philosopher's Stone: shortly before his death, Jack Crowley used a Philosopher's Stone to transform himself in a gigantic, gelatinous mass of tentacles that no longer even remotely resembled his original self.

Resurrection
Through an unknown form of human transmutation, the souls of dead humans may be called back from the afterlife and placed within the body of a golem by someone masterful in their creation. The resurrected individual will outwardly resemble their original human appearance, though this arrangement is only temporary as the golem body will eventually deteriorate, causing the resurrectee a great deal of pain. The only known individual resurrected through this process, Elma, reacted poorly to being resurrected and exhibited an intense desire to die and take her husband Jack Crowley with her.

Trivia

 * Oddly, the method in which humans may be revived in the form of golems would not possible within the manga or either of the anime.