Instead of its normal effect, you can choose to have your ability to channel energy heal or harm outsiders of your chosen Elemental subtype. You must make this choice each time you channel energy. If you choose to heal or harm creatures of your Elemental subtype, your channel energy has no effect on other creatures. The amount of Damage healed or dealt and the DC to halve the Damage is otherwise unchanged.

Elemental Channel (Earth)

General

Channel energy class feature.

You can gain this feat multiple times. Its effects do not stack. Each time you take this feat, it applies to a new Elemental subtype.