Monster: Synthelid (CR 16, Large Aberration)
You know how a fallen Mind Flayer colony typically spawns a feral Neothelid? What if the tadpoles took a different path? What if they merged, not into a berserking worm, but into a calm, patient mastermind?
The Synthelid is a psychic schemer who prefers to pull strings from the shadows, subtly guiding entire communities and shaping their beliefs and customs over the years. They use their glowing nodules to channel their innate psionic powers, blasting the minds of others with psychic energy to subjugate them to their will. I have always liked the concept behind the Neothelid, so I wanted to explore a different outcome, one that emphasizes the psionic mastery of its origins and draws inspiration from one of my favorite monsters, the Aboleth.
For Dungeon Masters seeking to give this extremely rare creature a more significant role in their campaigns, I have included lair actions and regional effects to warp the area surrounding its domain.
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