Three Heads (Ex): All of a Dugtrio's heads can operate independently, and it can attack with all three heads with a single partial action. Earthquake (Sp): One or more Dugtrios digging in a single area can generate an Earthquake spell with a caster level equal to the combined HD of the Dugtrios, centered anywhere within close range (25 feet plus 5 feet per 2 hit dice) of all participating Dugtrios. The more Dugtrios involved, the less time it takes to generate the Earthquake. The entire group must dig in the same place for at 3d6 rounds minus one round for each participating Dugtrio. After having done so, a Dugtrio cannot again participate in an Earthquake for 1d4 minutes.