燃え立つ大地

01/07/13

If any nonbasic lands are tapped for mana while a player is casting a spell or activating an ability, Burning Earth’s ability will trigger that many times and wait. When the player finishes casting that spell or activating that ability, Burning Earth’s triggered abilities are put on the stack on top of it. Burning Earth’s abilities will resolve first.

01/07/13

To tap a land for mana is to activate one of that land’s mana abilities that has in its activation cost and produces mana as it resolves.