Ankhegs

Overview
The ankheg is a burrowing monster with a taste for fresh meat. It is about 10 feet long and weighs about 800 pounds.

Appearance
An ankheg has six legs, and some specimens are yellow rather than brown. An ankheg resembles an enormous many-legged insect, its long antennae twitching in response to any movement around it. Its legs end in sharp hooks adapted for burrowing and grasping its prey, its powerful mandibles can snap a small tree in half.

Behaviors
The ankheg uses its powerful mandibles to dig winding tunnels deep beneath the ground. When it hun​​​​​​​ts, an ankheg burrows upward, waiting below the surface until its antennae detect movement from above. Then it bursts from the earth and. seizes prey in its mandibles, crushing and grinding while it secretes acidic digestive enzymes. These enzymes help dissolve a victim for easy swallowing, but the ankheg can also squirt acid to take down foes.

Although ankhegs receive a certain portion of their nutrients from the soil through which they burrow, they must supplement their diet with fresh meat. Pastures teeming with grazing livestock and forests rife with game are an ankheg's prime hunting grounds. Ankhegs are thus the bane of farmers and rangers everywhere.

As it burrows through earth, the ankheg leaves a narrow, partially collapsed tunnel in its wake. In these tunnels, one might find the remnants of molted ankheg chitin, hatched ankheg eggs, or the grisly remains of ankheg victims, including coins or other treasures scattered during the creature's attack.

References Taken From
http://www.d20srd.org/srd/monsters/ankheg.htm

https://www.dandwiki.com/wiki/5e_SRD:Ankheg

https://en.wikipedia.org/wiki/Ankheg