- Demonic-Undead Mimicry
- Necrodemon/Necrotic Demon Mimicry/Physiology
- Undead-Demon Mimicry/Physiology
- Undead-Demonic Mimicry/Physiology
- Undemon Mimicry/Physiology
User with this ability either is or can transform into a combination of an demon and an undead. Their presence is extremely unnatural and/or corrupt. They specialize in the raw power of unholy and necrotic energies for powerfully destructive effects.
- Demon Physiology
- Malefic Force Manipulation
- Undead Physiology
- Undead Pulse
- Certain hybrid types may still rely on their undead species need to feed on blood, life-force, flesh, etc.
- May be vulnerable to holy powers and artifacts.
- If resurrected, may lose access to undead powers.
- May corrupt the user's mind.
- May be weak to Purification.
- Marceline (Adventure Time); after being turned into a vampire.
- Hellhounds (Call of Duty Series)
- Hell Jason (Friday the 13th The Game)
- Purgatori (Chaos Comics)
- The Possessed (Doom)
- Zombiemen (Doom Series)
- Zombies (Doom 3 Series)
- Deadites (Evil Dead Series)
- Orcus (Forgotten Realms); before resurrection
- Visages (Forgotten Realms)
- Undead Demons (InuYasha)
- Bodyconian (Megami Tensei)
- Isabella Von Carstein (Warhammer Fantasy); after her resurrection in The End Times.