Rule evolution

Rule 509.3d

Previously numbered 509.4d, 509.5d.

Earliest archived Rules release: 2009-10-01 · 3 wording revisions · 2 renumberings

  1. Earliest archived Rules release509.4dDetails
    An ability that reads "Whenever [this creature] becomes blocked by a creature, . . ." triggers once for each creature that blocks the named creature. It will also trigger if an effect causes a creature to block the attacking creature, even if it had already been blocked that combat. It won't trigger if the creature becomes blocked by an effect rather than a creature.
  2. Wording changed509.4dDetails
    An ability that reads "Whenever [this creature] becomes blocked by a creature, . . ." triggers once for each creature that blocks the named creature. It will also trigger if an effect causes a creature to block the attacking creature, even if it had already been blocked that combat. It triggers if a creature is declared as a blocker for the attacking creature. It won't trigger if the creature becomes blocked by an effect rather than a creature.It will also trigger if an effect causes a creature to block the attacking creature, but only if it wasn't already blocking that attacking creature at that time. In addition, it will trigger if a creature is put onto the battlefield blocking that creature. It won't trigger if the creature becomes blocked by an effect rather than a creature.
  3. Renumbered509.4d → 509.5dDetails

    Previously
    5. Turn Structure
    509. Declare Blockers Step

    Then
    5. Turn Structure
    509. Declare Blockers Step

    An ability that reads “Whenever [this creature] becomes blocked by a creature, . . .” triggers once for each creature that blocks the named creature. It triggers if a creature is declared as a blocker for the attacking creature. It will also trigger if an effect causes a creature to block the attacking creature, but only if it wasn’t already blocking that attacking creature at that time. In addition, it will trigger if a creature is put onto the battlefield blocking that creature. It won’t trigger if the creature becomes blocked by an effect rather than a creature.
  4. Wording changed509.5dDetails
    An ability that reads "Whenever [thisa creature] becomes blocked by a creature, . . ." triggers once for each creature that blocks the named creature. It triggers if a creature is declared as a blocker for the attacking creature. It will also trigger if an effect causes a creature to block the attacking creature, but only if it wasn't already blocking that attacking creature at that time. In addition, it will trigger if a creature is put onto the battlefield blocking that creature. It won't trigger if the creature becomes blocked by an effect rather than a creature.
  5. Wording changed509.5dDetails
    An ability that reads "Whenever [a creature] becomes blocked by a creature, . . ." triggers once for each creature that blocks the namedspecified creature. It triggers if a creature is declared as a blocker for the attacking creature. It will also trigger if an effect causes a creature to block the attacking creature, but only if it wasn't already blocking that attacking creature at that time. In addition, it will trigger if a creature is put onto the battlefield blocking that creature. It won't trigger if the creature becomes blocked by an effect rather than a creature.
  6. Renumbered509.5d → 509.3dDetails

    Previously
    5. Turn Structure
    509. Declare Blockers Step

    Then
    5. Turn Structure
    509. Declare Blockers Step

    An ability that reads “Whenever [a creature] becomes blocked by a creature, . . .” triggers once for each creature that blocks the specified creature. It triggers if a creature is declared as a blocker for the attacking creature. It will also trigger if an effect causes a creature to block the attacking creature, but only if it wasn’t already blocking that attacking creature at that time. In addition, it will trigger if a creature is put onto the battlefield blocking that creature. It won’t trigger if the creature becomes blocked by an effect rather than a creature.

Current in the latest available Rules
Unchanged since 2026-08-07.