Lurking beth

A is a creature that remains hidden until a player walks over it. It then bursts upward out of the ground, dealing damage and applying an additional bleeding effect.

Multiple will appear together in clusters of  connected tiles. They are commonly found in Bethesda Susa.

You can attack and destroy a by force attacking (Ctrl+) into an empty square. If a is present in that square, you will attack it and a message will appear in the message log indicating that it was attacked and/or destroyed.