Ankheg is a Large monstrosity with unaligned alignment and Challenge Rating 2 in the 2024 SRD. This stat block includes AC 14, 45 hit points, speeds, traits, and actions.
Bite - Melee Attack Roll: +5 (with Advantage if the target is Grappled by the ankheg), reach 5 ft. Hit: 10 (2d6 + 3) Slashing damage plus 3 (1d6) Acid damage. If the target is a Large or smaller creature, it has the Grappled condition (escape DC 13).
Acid Spray - Dexterity Saving Throw: DC 12, each creature in a 30-foot-long, 5-foot-wide Line. Failure: 14 (4d6) Acid damage. Success: Half damage.