Earth bore is a variant of the move earth spell, one designed to drill short tunnels through hard stone and earth. The spell drills through hard stone at a rate of 5 feet per round, crushing about 10 cubic feet of material into fine gravel and detritus. The crushed material must be excavated and moved before the tunnel is actually accessible, though it is otherwise easily bagged and carted away. Move earth can also be used in conjunction with earth bore to remove the loose debris more quickly. The spell can make short cylindrical tunnels at any angle, vertical or horizontal, with a 5% chance per 10 feet of tunnel length that a tunnel will collapse during excavation. Using careful mine-shoring techniques, force spells or other reasonable protective measures cuts this chance in half.

Creatures within 10 feet of the boring area (the start of the tunnel) also stand in a tornado of violently churning rock which causes 3d6 hit points of damage per round (no save). Creatures of the earth subtype such as earth elementals and xorn are unaffected. This spell otherwise has no effect on creatures in combat. The spells fails to work on softer materials such as sand, soft clay, loose soil or mud. Earth bore is also stopped by lead, iron and similarly hard metals and can drill no further when striking such veins.