Past person. The thrall and the mind flayers that come from it keep their personality

Spellcasting. The Zombified Illithid  Thrall is a 1-level half spellcaster. Its spellcasting ability is [Wisdom] (spell save DC 10, +1 to hit with spell attacks). The [Zombified Illithid  Thrall] has following [Warlock] spells prepared:
Cantrips (at will): [Eldritch Blast ], [Psion link]
1st level (warlock slots)Fire bolt, [grease]

Psion overload. If a this monster fails three Psion attacks its brain will be devoured by the tadpole and turned into a mind flayer

Psion Burst. the Zombified Illithid Thrall will charge there Psion magic and send it in a big wave of energy hitting everything in 17 feet in front of it in a cone

Psion overcharge. Creates a sword made of Psion energy: +2  to hit, reach 10 ft., 1 target. Hit:  (1d10 + 8) [Psychic] damage.

Weaker mind blast. : Creates a dominating blast of psychic damage +1 to hit, range 80/320 ft., 1 target. Hit:  (3d4 + 1) [Psychic] damage.

Psionic Backlash. deal 1d4 psychic damage per spell level to a nearby enemy spellcaster when they cast a spell 

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