Earth Glide

You give the subject the ability to glide through earth and stone as easily as an earth elemental does.
The affected creature can glide through stone, dirt, or almost any other sort of earth except metal as easily as a fish swims through water.
Its burrowing leaves behind no tunnel or hole, nor does it create any ripple or other signs of its presence.
A move earth spell cast on an area containing the affected creature flings the creature back 30 feet and stuns the creature for 1 round unless it succeeds on a DC 15 Fortitude save.