#fantasymonsters

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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Monster: Thruknar (CR 4, Large Monstrosity)

Do you need a giant, mole-like creature for your next underground expedition? The Thruknar is a blind, subterranean hunter that uses tremorsense to track its prey before bursting from the earth. Its powerful claws can cleave through multiple enemies in a single swing and shatter the terrain beneath them.

Just make sure it doesn't get exposed to direct sunlight, as it isn't a big fan of the outside world…

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Earth’s Ravagers. A thruknar is a massive burrowing predator of the Underdark, resembling a mole swollen to monstrous size. Its fur grows in shaggy black or pallid albino tufts, and some sprout grotesque star-shaped tendrils around their snouts. Blind but sensitive to every tremor, they carve vast warrens that destabilize caverns and topple settlements. The earth is both their hunting ground and their weapon, and their sweeping claws can tear through stone as easily as flesh.

Gougers and Draft Beasts. Goblins and deep gnomes sometimes risk raising young thruknar, using them as living drills to chew through seams of ore and stone too hard for tools. Such tamed beasts are not companions but volatile laborers, demanding constant vigilance, bribes of food, and the threat of harsh discipline to keep them in check. A trained thruknar can gouge passages where even magic falters, making them both invaluable and feared.

Rivals of the Bulette. Few sounds chill the Underdark like the clash of a thruknar and a bulette. Both creatures feed and burrow through the same strata, and each sees the other as an invader. When they meet, their conflict can collapse entire cavern systems, leaving trails of destruction behind them. Miners and caravans caught between the two face not only the predators but the wrath of the crumbling ground.g ground.

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