Magic: the Gathering
( Comprehensive rules )


Contents Glossary

5.  Turn Structure

509.  Declare Blockers Step


509.1  First, the defending player declares blockers. This turn-based action doesnt use the stack. To declare blockers, the defending player follows the steps below, in order. If at any point during the declaration of blockers, the defending player is unable to comply with any of the steps listed below, the declaration is illegal; the game returns to the moment before the declaration (see rule 720, "Handling Illegal Actions").

509.1a  The defending player chooses which creatures that he or she controls, if any, will block. The chosen creatures must be untapped. For each of the chosen creatures, the defending player chooses one creature for it to block thats attacking him, her, or a planeswalker he or she controls.

509.1b  The defending player checks each creature he or she controls to see whether its affected by any restrictions (effects that say a creature cant block, or that it cant block unless some condition is met). If any restrictions are being disobeyed, the declaration of blockers is illegal. A restriction may be created by an evasion ability (a static ability an attacking creature has that restricts what can block it). If an attacking creature gains or loses an evasion ability after a legal block has been declared, it doesnt affect that block. Different evasion abilities are cumulative.

Example: An attacking creature with flying and shadow cant be blocked by a creature with flying but without shadow.

509.1c  The defending player checks each creature he or she controls to see whether its affected by any requirements (effects that say a creature must block, or that it must block if some condition is met). If the number of requirements that are being obeyed is fewer than the maximum possible number of requirements that could be obeyed without disobeying any restrictions, the declaration of blockers is illegal. If a creature cant block unless a player pays a cost, that player is not required to pay that cost, even if blocking with that creature would increase the number of requirements being obeyed.

Example: A player controls one creature that "blocks if able" and another creature with no abilities. If a creature with menace attacks that player, the player must block with both creatures. Having only the first creature block violates the restriction created by menace (the attacking creature cant be blocked except by two or more creatures). Having only the second creature block violates both the menace restriction and the first creatures blocking requirement. Having neither creature block fulfills the restriction but not the requirement.

509.1d  If any of the chosen creatures require paying costs to block, the defending player determines the total cost to block. Costs may include paying mana, tapping permanents, sacrificing permanents, discarding cards, and so on. Once the total cost is determined, it becomes "locked in." If effects would change the total cost after this time, ignore this change.

509.1e  If any of the costs require mana, the defending player then has a chance to activate mana abilities (see rule 605, "Mana Abilities").

509.1f  Once the player has enough mana in his or her mana pool, he or she pays all costs in any order. Partial payments are not allowed.

509.1g  Each chosen creature still controlled by the defending player becomes a blocking creature. Each one is blocking the attacking creatures chosen for it. It remains a blocking creature until its removed from combat or the combat phase ends, whichever comes first. See rule 506.4.

509.1h  An attacking creature with one or more creatures declared as blockers for it becomes a blocked creature; one with no creatures declared as blockers for it becomes an unblocked creature. This remains unchanged until the creature is removed from combat, an effect says that it becomes blocked or unblocked, or the combat phase ends, whichever comes first. A creature remains blocked even if all the creatures blocking it are removed from combat.

509.1i  Any abilities that trigger on blockers being declared trigger. See rule 509.4 for more information.

509.2  Second, for each attacking creature thats become blocked, the active player announces that creatures damage assignment order, which consists of the creatures blocking it in an order of that players choice. (During the combat damage step, an attacking creature cant assign combat damage to a creature thats blocking it unless each creature ahead of that blocking creature in its order is assigned lethal damage.) This turn-based action doesnt use the stack.

Example: Vastwood Gorger is blocked by Llanowar Elves, Runeclaw Bear, and Serra Angel. Vastwood Gorgers controller announces the Vastwood Gorgers damage assignment order as Serra Angel, then Llanowar Elves, then Runeclaw Bear.

509.2a  During the declare blockers step, if a blocking creature is removed from combat or a spell or ability causes it to stop blocking an attacking creature, the blocking creature is removed from all relevant damage assignment orders. The relative order among the remaining blocking creatures is unchanged.

509.3  Third, for each blocking creature, the defending player announces that creatures damage assignment order, which consists of the creatures its blocking in an order of that players choice. (During the combat damage step, a blocking creature cant assign combat damage to a creature its blocking unless each creature ahead of that blocked creature in its order is assigned lethal damage.) This turn-based action doesnt use the stack.

509.3a  During the declare blockers step, if an attacking creature is removed from combat or a spell or ability causes it to stop being blocked by a blocking creature, the attacking creature is removed from all relevant damage assignment orders. The relative order among the remaining attacking creatures is unchanged.

509.4  Fourth, the active player gets priority. (See rule 116, "Timing and Priority.")

509.4a  Any abilities that triggered on blockers being declared or that triggered during the process described in rules 509.13 are put onto the stack before the active player gets priority; the order in which they triggered doesnt matter. (See rule 603, "Handling Triggered Abilities.")

509.5  Triggered abilities that trigger during the declare blockers step may have different trigger conditions.

509.5a  An ability that reads "Whenever [this creature] blocks, . . ." generally triggers only once each combat for that creature, even if it blocks multiple creatures. It triggers if the creature is declared as a blocker. It will also trigger if that creature becomes a blocker as the result of an effect, but only if it wasnt a blocking creature at that time. (See rule 509.1g.) It wont trigger if the creature is put onto the battlefield blocking.

509.5b  An 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 wasnt already blocking that attacking creature at that time. It wont trigger if the creature is put onto the battlefield blocking.

509.5c  An ability that reads "Whenever [this creature] becomes blocked, . . ." generally triggers only once each combat for that creature, even if its blocked by multiple creatures. It will trigger if that creature becomes blocked by at least one creature declared as a blocker. It will also trigger if that creature becomes blocked by an effect or by a creature thats put onto the battlefield as a blocker, but only if the attacking creature was an unblocked creature at that time. (See rule 509.1h.)

509.5d  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 wasnt 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 wont trigger if the creature becomes blocked by an effect rather than a creature.

509.5e  If an ability triggers when a creature blocks or becomes blocked by a particular number of creatures, the ability triggers if the creature blocks or is blocked by that many creatures when blockers are declared. Effects that add or remove blockers can also cause such abilities to trigger. This applies to abilities that trigger on a creature blocking or being blocked by at least a certain number of creatures as well.

509.5f  If an ability triggers when a creature with certain characteristics blocks, it will trigger only if the creature has those characteristics at the point blockers are declared, or at the point an effect causes it to block. If an ability triggers when a creature with certain characteristics becomes blocked, it will trigger only if the creature has those characteristics at the point it becomes a blocked creature. If an ability triggers when a creature becomes blocked by a creature with certain characteristics, it will trigger only if the latter creature has those characteristics at the point it becomes a blocking creature. None of those abilities will trigger if the relevant creatures characteristics change to match the abilitys trigger condition later on.

Example: A creature has the ability "Whenever this creature becomes blocked by a white creature, destroy that creature at end of combat." If the creature becomes blocked by a black creature that is later turned white, the ability will not trigger.

509.5g  An ability that reads "Whenever [this creature] attacks and isnt blocked, . . ." triggers if no creatures are declared as blockers for that creature. It will trigger even if the creature was never declared as an attacker (for example, if it entered the battlefield attacking). It wont trigger if the attacking creature is blocked and then all its blockers are removed from combat.

509.6  If a spell or ability causes a creature on the battlefield to block an attacking creature, the active player announces the blocking creatures placement in the attacking creatures damage assignment order. The relative order among the remaining blocking creatures is unchanged. Then the defending player announces the attacking creatures placement in the blocking creatures damage assignment order. The relative order among the remaining attacking creatures is unchanged. This is done as part of the blocking effect.

509.7  If a creature is put onto the battlefield blocking, its controller chooses which attacking creature its blocking as it enters the battlefield (unless the effect that put it onto the battlefield specifies what its blocking), then the active player announces the new creatures placement in the blocked creatures damage assignment order. The relative order among the remaining blocking creatures is unchanged. A creature put onto the battlefield this way is "blocking" but, for the purposes of trigger events and effects, it never "blocked."

Example: Giant Spider is blocked by Canyon Minotaur. The defending player casts Flash Foliage, which creates a Saproling creature token blocking the Giant Spider. Giant Spiders controller announces the Giant Spiders damage assignment order as the Saproling token, then Canyon Minotaur.

509.7a  If the effect that puts a creature onto the battlefield blocking specifies its blocking a certain creature and that creature is no longer attacking, the creature is put onto the battlefield but is never considered a blocking creature. The same is true if the controller of the creature thats put onto the battlefield blocking isnt a defending player for the specified attacking creature.

509.7b  A creature thats put onto the battlefield blocking isnt affected by requirements or restrictions that apply to the declaration of blockers.



       5.  Turn Structure
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5.  Turn Structure       
510. Combat Damage Step  >>
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