Armor Class 14
Hit Points 137 (25d8 + 25)
Speed 30 ft.
Saving Throws INT +6, WIS +7
Skills Arcana +6, Perception +7, Religion +6
Senses Darkvision 90 ft., passive Perception 17
Languages Common, Deep Speech; telepathy 30 ft.
Challenge 8
Multiattack. The cultist makes two Tentacle Lash attacks. It can replace any attack with a use of Mind Rot.
Tentacle Lash. m +7, reach 10 ft. Hit: 7 (1d6 + 4) Slashing damage plus 14 (4d6) Psychic damage. If the target is a Large or smaller creature, it has the Grappled condition (escape DC 14) from one of two tentacles, and it has the Restrained condition until the grapple ends.
Mind Rot. wis DC 15, one creature the cultist can see within 90 feet. 27 (6d8) Psychic damage, and the target has the Poisoned condition until the start of the cultist's next turn. Half damage only.
Monster Manual (2024), p. 86