The ankhegs' innards are eye-watering, caustic black messes, that Gildrim quickly learns not to touch, after a few minor burns. His dagger is a worthless lump of dull, twisted metal by the time he has finished going through the remains.
He finds in each bug a long, fairly straight tube leading from mouth to opposite extremities, which seems like it must surely be digestive in nature. When cut open, they contain more caustic black ichor, smelling slightly different than the "blood". Out of one of the stomachs, an oblong disk of corroded, blackened metal falls. On closer inspection, the disk has two rivets through one of its long ends, and a short metal post with a ball on it protruding from the other end; a design sometimes used for belt buckles.
[sblock=knowledge(nature) DC 12 or Bardic knowledge DC 15]Many insects eat by covering their food with digestive enzymes, waiting for it to liquefy, and then drinking the resulting goo. [/sblock]