Ankheg

Ankhegs are large insectoid, underground creatures often preying on beasts of burden in the night. The desert variant of ankhegs, known to exist in Marquet, are called sandkhegs.

Appearance
An ankheg is a large, 8–9-foot-long, cockroach-like creature with long antennae. The length of the body consists of segmented armor like plates held together by hard, yellowish muscle sinew. Several legs protrude out of its body; of these their front pair are adapted with sharp hooks for burrowing and for grasping prey. Its head has large, powerful mandibles that can snap a small tree in half, and its throat contains a basketball-sized sac which produces a dark green acid for spitting out at prey. These creatures have light green blood.

Abilities

 * Bite: Melee weapon attack against one target with +5 to hit and reach 5 of ft. If hits, deals 10 (2d6 + 3) slashing damage plus 3 (1d6) acid damage. If the target is a Large or smaller creature, it is grappled (escape DC 13). Until this grapple ends, the ankheg can bite only the grappled creature and has advantage on attack rolls to do so.
 * Acid Spray (recharge 6): The ankheg spits acid in a line that is 30 feet long and 5 feet wide, provided that it has no creature grappled. Each creature in that line must make a DC 13 Dexterity saving throw, taking 10 (3d6) acid damage on a failed save, or half as much damage on a successful one.

Useful components

 * The hard, yellowish muscle sinew and tendons under its segmented chitinous armor could be used to make strong cord.
 * Basketball-sized, acid-producing sacs.
 * The desert-based variant of ankhegs are used to create the extremely strong alcoholic beverage, Sandkheg's Hide.

Campaign 1: Vox Machina
Vox Machina fought an ankheg colony in the Herethis platinum mines near Deastok in. The ankhegs had been drawn there by Symphior, a corrupted planetar.

Campaign 2: The Mighty Nein
While the Mighty Nein were heading north from Hupperdook towards Shadycreek Run in an effort to catch the Iron Shepherds and rescue Jester, Fjord, and Yasha from enslavement, they decided to not take the path through towards the crossroads but instead take the presumed quicker path around the forest. Making their way around the forest, they discovered an abandoned homestead that was around 200 feet from the northern edge of the Crispvale Thicket. After making camp the party prepared to take a rest; they sensed localized rumbling and the horses being distressed, and the party was assaulted by group of ankhegs that emerged out of the ground and spat acid at their horses, leading to the deaths of Water Closet and Loo.

Exandria Unlimited
The Crown Keepers found an adult ankheg in a cage on the Blightstar, and found a baby (pupa) ankheg in a criminal organization's warehouse.