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, a golem's body was black as lead. They possess a limited level of intelligence, with an ability to grasp basic human speech. Like homunculi, golems require souls of their own to provide them with animating power, though Jack Crowley animated his golems using the power of the Philosopher's Stone in Lebis.

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.

Soul Binding
It is possible to use golems as receptacles for soul binding, though this is dangerous due to the instability of the golem body. Both the body and the soul bond will invariably deteriorate, degenerating into insanity and extreme physical mutation over a prolonged period before finally collapsing back into inert mud. Needless to say, this is an extremely painful process for the bonded soul. The degeneration can be exacerbated with the Philosopher's Stone: shortly before his death, Jack Crowley used a Philosopher's Stone to transform himself into a gigantic, mindless mass of gelatinous tentacles that no longer possessed any semblance of his former 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 as it does after soul binding, causing the resurrectee a great deal of anguish.

The only known individual resurrected through this process, and more than once at that, was Elma by her husband Jack Crowley. Elma reacted poorly to being resurrected: her physical features twisted grotesquely and her mind developed a deranged split personality. She sought out the Elric brothers for assistance and their efforts ultimately led to the deaths of both herself and Crowley, which was probably her plan all along.

Trivia

 * By the laws of alchemy in the Fullmetal Alchemist manga and Fullmetal Alchemist anime the method in which humans may be resurrected (in this case in the bodies of golems) should not be possible, as alchemy cannot create or manipulate the soul of someone who is deceased. The process Elma was subjected to caused her great suffering and eventually drove her to murder-suicide by proxy. In a roundabout way, this outcome conforms to the law that resurrection is impossible: while she existed among the living, Elma remained metaphorically dead and not only returned to that state but also ensured the mutual death of her would-be resurrectionist.