Undead Guard (5e Creature)
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Medium humanoid (any race), any evil alignment
Undead Defender. If the guard dies, it rises at the end of its next turn as a zombie, unless the guard is restored to life or its body is destroyed.
Scimitar. Melee Weapon Attack: +3 to hit, reach 5 ft., one target. Hit: 4 (1d6 + 1) slashing damage.
Undead guards serve cults dedicated to fiends and dark gods who seek to create undead. Their bodies are covered in runes of evil etched into their very flesh, which causes their bodies to animate as shambling undead when they die.