Helgot Servant Psion (5e Creature)
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Medium humanoid (any race), unaligned
Impenetrable Mind. The servant has advantage on saving throws against any attack that would attempt to read its thoughts, determine its alignment, or otherwise affect its mind. If the servant succeeds on any such save, the creature which imposed the saving throw takes 3 (1d4 + 1) psychic damage.
Slam. Melee Weapon Attack: +3 to hit, reach 5 ft., one target. Hit: 5 (1d8 + 1) bludgeoning damage.
Dread Aura (Recharge 6). The servant emits an aura of psychic energy around it in a 20-foot radius around it. Each creature in that area must make a 11 Intelligence saving throw. On a failed save, a creature takes 10 (3d6) psychic damage and is blinded. On a successful save, the creature takes half as much damage and isn't blinded.
A normal being enslaved by the venom of the helgot, forced into servitude as a mindless husk.