Burrow (Ex)
Source: Advanced Player's Guide, p. 63
An eidolon grows thick and gnarled claws, allowing it to move through the earth. The eidolon gains a burrow speed equal to 1/2 its base speed. It can use this speed to move through dirt, clay, sand, and earth. It does not leave a hole behind, nor is its passage marked on the surface. The summoner must be at least 9th level before selecting this evolution.