Floating Skull (5e Creature)
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Tiny undead, lawful evil
Bite. Melee Weapon Attack: +2 to hit, reach 5 ft., one target. Hit: 1 bludgeoning damage. After a successful hit, a floating skull remains clamped onto its victim, dealing damage automatically each turn thereafter. As an action, a creature may attempt a DC 5 Strength check to pry it loose.
Floating skulls are exactly so, skulls that float. They are occasionally posted as decoys by demiliches, or disguised with illusions so that they resemble flameskulls. A necromancer that has resorted to using floating skulls against his enemies is either biding for time or has run out of more potent undead soldiers.
Undead Nature. A floating skull does not require air, food, drink, or sleep.