Rule evolution
Rule 509.3b
Previously numbered 509.4b, 509.5b.
Earliest archived Rules release: 2009-10-01 · 2 wording revisions · 2 renumberings
Earliest archived Rules release509.4bDetails
An ability that reads "Whenever [this creature] blocks a creature, . . ." triggers once for each attacking creature the creature with the ability blocks. It triggers only if the creature is declared as a blocker.
Wording changed509.4bDetails
An ability that reads "Whenever [this creature] blocks a creature, . . ." triggers once for each attacking creature the creature with the ability blocks. It triggers
onlyif the creature is declared as a blocker. It will also trigger if an effect causes that creature to block an attacking creature, but only if it wasn't already blocking that attacking creature at that time. It won't trigger if the creature is put onto the battlefield blocking.Renumbered
509.4b→ 509.5bDetailsPreviously
5. Turn Structure
509. Declare Blockers StepThen
5. Turn Structure
509. Declare Blockers StepAn ability that reads “Whenever [this creature] blocks a creature, . . .” triggers once for each attacking creature the creature with the ability blocks. It triggers if the creature is declared as a blocker. It will also trigger if an effect causes that creature to block an attacking creature, but only if it wasn’t already blocking that attacking creature at that time. It won’t trigger if the creature is put onto the battlefield blocking.
Wording changed509.5bDetails
An ability that reads "Whenever [
thisa creature] blocks a creature, . . ." triggers once for each attacking creature the creature with the ability blocks. It triggers if the creature is declared as a blocker. It will also trigger if an effect causes that creature to block an attacking creature, but only if it wasn't already blocking that attacking creature at that time. It won't trigger if the creature is put onto the battlefield blocking.Renumbered
509.5b→ 509.3bDetailsPreviously
5. Turn Structure
509. Declare Blockers StepThen
5. Turn Structure
509. Declare Blockers StepAn ability that reads “Whenever [a creature] blocks a creature, . . .” triggers once for each attacking creature the creature with the ability blocks. It triggers if the creature is declared as a blocker. It will also trigger if an effect causes that creature to block an attacking creature, but only if it wasn’t already blocking that attacking creature at that time. It won’t trigger if the creature is put onto the battlefield blocking.