Ash Plague Zombie

Ash Plague Aura. While Bloodied, the zombie emanates an aura in a 5-foot Emanation. Constitution Saving Throw: DC 13, each creature that starts its turn in the aura. Failure: The target has the Poisoned condition and can't regain Hit Points until the end of its next turn. Success: The target is immune to this zombie's aura for 24 hours.

Undead Fortitude. If damage reduces the zombie to 0 Hit Points, it makes a Constitution saving throw (DC 5 plus the damage taken) unless the damage is Radiant or from a Critical Hit. On a successful save, the zombie drops to 1 Hit Point instead.

Slam. Melee Attack Roll: +5, reach 5 ft. Hit: 7 (1d8 + 3) Bludgeoning damage.

Toxic Burst. Trigger: The zombie takes damage. Response–Constitution Saving Throw: DC 13, each creature in a 5-foot Emanation originating from the zombie. Failure: 9 (2d8) Poison damage, and the target has Disadvantage on saving throws until the end of the zombie's next turn. Success: Half damage only.