These creatures come in various forms, with many being shapeshifters. In the TV series, the AMP classifies them into three main categories:
* Category III: Low-level entities that are little more than animals. They often resemble snakes, mantas, or other animals.
* Category II: Beings with slightly less than human intelligence and modest magical abilities. Their appearances vary greatly. These beings can usually summon various Category III Lucifer Hawks to act as their "minions."
* Category I: Typically somewhat humanoid with magical powers comparable to the strongest human mages. At least as intelligent as humans, these beings are very eloquent and prone to engaging in mind games, as depicted in the anime.
* Category IV: Human-Lucifer Hawk hybrids. This is not an actual category in the AMP's classification; it only appears in an illusion created by Ganossa Maximillian to trap Katsumi Liqueur. She and the Cheyenne sisters are the only known members of this class.
The more powerful Lucifer Hawks can assume human form, while large groups of lower-level ones can take on the appearance of large objects, such as the AMP's Simurgh command vehicle. Lucifer Hawks can merge with physical objects like buildings or computers. The stronger ones have significant regenerative abilities, but ordinary handguns can kill the weaker ones.
Lucifer Hawks are capable of breeding with humans, as evidenced by the Cheyenne sisters. According to Grospoliner, Katsumi (and possibly other mages) have distant blood ties to the Lucifer Hawks from liaisons that occurred many generations ago.
