Rules glossary
609.7 Some effects apply to damage from a source—for example, “The next time a red source of your choice would deal damage to you this turn, prevent that damage.”
- 609.7a If an effect requires a player to choose a source of damage, they may choose a permanent; a spell on the stack (including a permanent spell); any object referred to by an object on the stack, by a replacement or prevention effect that’s waiting to apply, or by a delayed triggered ability that’s waiting to trigger (even if that object is no longer in the zone it used to be in); or a face-up object in the command zone. A source doesn’t need to be capable of dealing damage to be a legal choice. The source is chosen when the effect is created. If the player chooses a permanent, the effect will apply to the next damage dealt by that permanent, regardless of whether it’s combat damage or damage dealt as the result of a spell or ability. If the player chooses a permanent spell, the effect will apply to any damage dealt by that spell and any damage dealt by the permanent that spell becomes when it resolves.
- 609.7b Some effects from resolved spells and abilities prevent or replace damage from sources with certain properties, such as a creature or a source of a particular color. When the source would deal damage, the “shield” rechecks the source’s properties. If the properties no longer match, the damage isn’t prevented or replaced. If for any reason the shield prevents no damage or replaces no damage, the shield isn’t used up.
- 609.7c Some effects from static abilities prevent or replace damage from sources with certain properties. For these effects, the prevention or replacement applies to sources that are permanents with that property and to any sources that aren’t on the battlefield that have that property.