Ankheg

Like big bugs? Can’t get past the absurd notion of a landshark?  Good news: the ankheg is available for all your burrowing monster needs.

Plains halflings build sod-topped burrows to hide their villages from marauders.  But they must also keep the ankhegs out, so buried rings of stone surround each village.  Nevertheless, assaults by the bugs are still common, and anyone seeking a halfling guide must usually pay in ankheg heads to get the booking.

Formerly reliable desert oases are drying up.  The culprits are desert ankhegs (Huge advanced specimens) collapsing wells and boring into aquifers.  They seem to be guided by some higher intelligence.  But in a desert, clean water is sacred, so determining a motive behind the vandalism will be even more difficult than stopping it.

The Burnt Faces orc tribe sends ankhegs into battle.  (These orcs are not particularly good at riding them, but manage to goad them forward with chains and crops nonetheless.)  They all bear acid scars on their faces, a testament to their ankhegs’ acid spit.

—Pathfinder Bestiary 2 29

Apparently, ankhegs date all the way back to Dragon #5.  That’s pretty cool.