Tenueloth

"We're your first, last and only line of defense against the worst scum of the universe."

- Wilhelm the Blacksmith, in his popular song about fighting Tenueloths

From a distance, an undisguised Tenueloth resembles a well-dressed, tall and thin man. However, Tenueloths move with a snake-like dexterity and flexibility, and have several distinctly reptillian features such as patches of scaly skin and snake-like eyes, which they often hide behind long sleeves and dark glasses.

Tenueloths are experts in infiltration and thievery. They're easily the least conspicuous of the yugoloths, and can disguise themselves at will. They are as suave and convincing in conversation as any bard, and don't need magic to be charming. They're also fluent with all manner of humanoid languages, and can easily pick up new languages and abilities if a job demands it.

Between their incredible mobility, surprising strength, deadly weapons and innate magic, tenueloths also serve as extraordinarily effective assassins. Tenueloths are known to leap into windows on second stories and shatter the glass with a single deft kick; many a window to a king or minister's bedroom has been reinforced to prevent a stream of six hired tenueloths from breaking, entering, then slaughtering everyone in a room with poison gas and plasma bursts.

The easiest way to identify a disguised tenueloth is to challenge one to an arm wrestling competition and watch its arm. Under stress, a tenueloth's arm will bend and buckle in uncanny ways as they do not have elbows; rather, their arms are built with vertebrae similar to a snake's body. Tenueloths are aware of this method used to identify them, and will avoid any physically straining activity that might reveal their nature.

Variant: Acidic Tenueloth Some tenueloths are adapted to use acid instead of poison. Such tenueloths are immune to acid damage as well as poison, know the spell Acid Splash instead of Poison Spray, and replace their Spit Poison ability with the following: Spit Acid (Recharge 5-6). The tenueloth spits a cloud of acidic gas, centered on a point it can see within 90 feet. The cloud has a radius of 10 feet and lasts until the end of the tenueloth's next turn. Any creature that passes through or starts its turn in the cloud must succeed on a DC 13 Dexterity saving throw or suffer acidic corrosion for 3 rounds. While corroded in this manner, a creature has disadvantage on attack rolls and takes 1 point of acid damage whenever it takes an action, bonus action, reaction and for every 5 feet it moves. This corrosion ends early if the creature has its hit points restored by magic. A creature resistant to acid damage does not suffer damage from this, and a creature immune to acid damage is immune to this effect.

Pictured here: a sneering, recently summoned tenueloth, contemplating its reinforced glass summoning circle

Credit: XCOM: Enemy Unknown