Boulderfall | Magic: The Gathering
Formats Boulderfall is Legal in
Official Oracle Text for Boulderfall
—Eocles, oracle of Purphoros
Official Rulings for Boulderfall
9/15/2013 : If some but not all of Boulderfall’s targets become illegal, you can’t change the division of damage. Damage that would have been dealt to illegal targets simply isn’t dealt.
9/15/2013 : You can’t deal damage to both a player and a planeswalker that player controls using Boulderfall. You also can’t deal damage to more than one planeswalker controlled by the same player. If you choose to redirect the damage being dealt to a player to a planeswalker, you must redirect all the damage to a single planeswalker.
9/15/2013 : If an effect creates a copy of Boulderfall, the division of damage and number of targets can’t be changed. The effect that creates the copy may allow you to change targets, however.