Akuma (アクマ, Akuma lit. demon) take up the majority of the Earl's army and serve as the "foot soldiers". When one is mourning for a lost relative or friend, the Earl appears offering to resurrect that member for them. However, the raised soul becomes the power source for the Earl's weapon and must obey his orders. The Noah Family has also absolute control over the Akuma, regardless of their levels.
Akuma "wear" the skin of the one who resurrected them. They use this to blend in, as Exorcists cannot tell Akuma from human with the exception of Allen.
The Akuma share a metal core made of dark matter that resembles a simplified human skeleton. Their blood also contains a blood virus, which rapidly travels through the victim's body, marking it with pentacles. The virus can be spread by blood bullets of a high caliber shot by the level one Akuma. Eventually, the body crumbles into dust and gives off a poisonous gas. However, parasitic Innocence users can force the virus to recede and nullify it, giving them a near immunity resistance.
Level 0 is the Akuma right after being created. It is only the metal skeleton which is presented similarly to a model kit format when still unoccupied by a soul. The human soul is the dominant personality, but it is still bound to the Earl's control. The ends of the arms varies from Akuma to Akuma. The separate 'bones' are not connected in any way, but rather hover near where they would be connected. After a soul occupies the skeleton, a pentagon along with its host's name below it will be inscribed on the forehead of the skeletal structure. No matter how inhuman an Akuma becomes upon reaching level 2, the level 0 form remains as its skeleton.
Level 1EditLevel 1 consists of a floating ball shaped creature with dozens of gun barrels protruding from it. The gun barrels are flexible and can be bent to face any desired angle without affecting its firing capabilities. The souls inside a Level 1 Akuma have the bodies and clothes of their original forms. However, their faces are rather distorted and there is a chain around their necks expressing intense pain and sadness of the trapped soul. Level 1 akuma exhibit somewhat a transition from deteriorating human personality to an evil personality for level 2 later on as observed in their increasing obsession to simply kill and may, hence, show zombie like behaviour in their human form. A Level 1 Akuma will advance to a Level 2 once it has fulfilled a substantial quota of kills of humans and exorcist.
The bullets shot by the Akuma contain a poisonous virus. The bullets made of the blood of the Akuma is deadly to the human flesh, spreading rapidly in the form of pentacles (dark purple stars) upon hitting someone, cracking and corroding the human's body, leading them to crumble to pieces. Only those with a parasitic Innocence like Allen Walker, Arystar Krory or Suman Dark can heal the virus.
Level 1.5 is not an actual level per say, it is more of a mid-way point for a Level 1 Akuma. The only difference is that the Akuma becomes rounder and more spherical, with the ends of the barrels on the surface. Their facial expressions appears to show more instances of emotions closing in to a personality as of a Level 2
Level 2EditLevel 2 produces a dramatic change. They develop a unique ability and a sense of self. Level 2 Akuma are capable of intelligent thought and are largely independent, though they still maintain unquestionable loyalty to the Millennium Earl and the Clan of Noah. The souls of Level 2 Akuma seem to become more deteriorated. The souls inside of these Akuma can't seem to be identified at all and are in a fetal position, wrapped from head to toe in bandages. Level 2 Akuma come in all shapes and sizes and they have no common appearance. Thus far, Level 2 is the only state in evolution where appearance is varied as 1, 3, and 4 all maintain the same shape with only subtle differences. They also have different powers, such as copying a person's appearance emitting "ice fire" which hurts worse than normal fire, creating blades of air, emitting destructive sound waves, and creating bubbles that absorb water from everything they touch. Some Level 2 Akuma even carry modern day weaponry such as homing missiles and various types of firearms that resemble machine guns and so on, as observed in the manga. After murdering enough people, it can evolve to Level 3.
Level 3 brings perhaps the most terrifying changes of any previous stage. Regardless of their appearance in Level 2, all level 3 Akuma become bipedal, roughly 8 to 9 feet tall, with sharp jagged teeth, and wear what looks like medieval armor that covers most of their bodies. The only difference between each other is the color of their armor and the helmet design of each one is unique. In addition to this, they receive a massive power boost. A Level 3 Akuma is easily capable of standing up to multiple Exorcists in combat and usually has an extremely powerful ability in addition to its greatly improved strength and speed. Their abilities seem to revolve around the use of Dark Matter, the polar opposite of Innocence. The souls embedded in the Level 3 Akuma are near gone and appear as a floating dark mass with eyes.