When do you pay the extra Energy for Shadows of the Dahan? <i>("Whenever you use a Power, you may pay 1 Energy to target a land with Dahan...")</i>
When do you pay the extra Energy for Shadows of the Dahan? ("Whenever you use a Power, you may pay 1 Energy to target a land with Dahan...")
When you use the Power - i.e., resolve its text effects. You don't have to choose a Power's target until you actually use it.
