The ability to alter dead beings, controlling either their bodies or their spirits.
Typically, necromancy is related to the ability to bring beings back to life or into a state of undeath, such as is the case with zombies, vampires, etc. It is considered a far more malevolent form of Magic but is not always related. While these abilities are not always considered Necromancy, it will almost always be considered some form of Necromancy.
Resurrection: Necromancers can use their ability to bring fallen entities back to life through unknown means.
Immortality: Capable of converting others and themselves into a state of undeath, thus making them immortal to some degree.
Energy Manipulation: Similar to the above, certain users can use life or death energies to form attacks or other abilities.
Soul Manipulation: Users typically can bypass traditional durability by attacking the souls of their enemies, making almost anyone they face vulnerable.