General Rulings - 508

• 508.1 - First, the active player declares attackers. This turn-based action doesn't use the stack. To declare attackers, the active player follows the steps below, in order. If at any point during the declaration of attackers, the active player is unable to comply with any of the steps listed below, the declaration was illegal; the game returns to the moment before the declaration (see Rule 714, "Handling Illegal Actions"). [CompRules 2009/07/08]
• 508.1a - The active player chooses which creatures that he or she controls, if any, will attack. The chosen creatures must be untapped, and each one must either have haste or have been controlled by the active player continuously since the turn began. [CompRules 2009/07/08]
• 508.1b - If the defending player controls any planeswalkers, or the game allows the active player to attack multiple other players, the active player announces which player or planeswalker each of the chosen creatures is attacking. [CompRules 2009/07/08]
• 508.1c - The active player checks each creature he or she controls to see whether it's affected by any restrictions (effects that say a creature can't attack, or that it can't attack unless some condition is met). If any restrictions are being disobeyed, the declaration of attackers is illegal. [CompRules 2009/07/08]
  Example: A player controls two creatures, each with a restriction that states "<-This creature-> can't attack alone." It's legal to declare both as attackers. [CompRules 2009/07/08]
• 508.1d - The active player checks each creature he or she controls to see whether it's affected by any requirements (effects that say a creature must attack, or that it must attack 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 attackers is illegal. Tapped creatures and creatures with unpaid costs to attack are exempt from effects that would require them to attack. [CompRules 2009/07/08]
  Example: A player controls two creatures: one that "attacks if able" and one with no abilities. An effect states, "No more than one creature can attack each turn." The only legal attack is for just the creature that "attacks if able" to attack. It's illegal to attack with the other creature, attack with both, or attack with neither. [CompRules 2009/07/08]
• 508.1e - If any of the chosen creatures have banding or a "bands with other" ability, the active player announces which creatures, if any, are banded with which. (See Rule 702.19, "Banding.") [CompRules 2009/07/08]
• 508.1f - The active player taps the chosen creatures. Tapping a creature when it's declared as an attacker isn't a cost; attacking simply causes creatures to become tapped. [CompRules 2009/07/08]
• 508.1g - If any of the chosen creatures require paying costs to attack, the active player determines the total cost to attack. 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. [CompRules 2009/07/08]
• 508.1h - If any of the costs require mana, the active player then has a chance to activate mana abilities (see Rule 605, "Mana Abilities"). [CompRules 2009/07/08]
• 508.1i - 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. [CompRules 2009/07/08]
• 508.1j - Each chosen creature still controlled by the active player becomes an attacking creature. It remains an attacking creature until it's removed from combat or the combat phase ends, whichever comes first. See Rule 506.4. [CompRules 2009/07/08]
• 508.2 - Second, any abilities that triggered on attackers being declared go on the stack. (See Rule 603, "Handling Triggered Abilities.") [CompRules 2009/07/08]
• 508.2a - Abilities that trigger on a creature attacking trigger only at the point the creature is declared as an attacker. They will not trigger if a creature attacks and then that creature's characteristics change to match the ability's trigger condition. [CompRules 2009/07/08]
  Example: A permanent has the ability "Whenever a green creature attacks, destroy that creature at end of combat." If a blue creature attacks and is later turned green, the ability will not trigger. [CompRules 2009/07/08]
• 508.3 - Third, the active player gets priority. Players may cast spells and activate abilities. [CompRules 2009/07/08]
• 508.4 - Effects from a creature that refer to a defending player refer only to the defending player it's attacking (if it's attacking a player) or the controller of the planeswalker it's attacking (if it's attacking a planeswalker). [CompRules 2009/07/08]
• 508.5 - If a creature is put onto the battlefield attacking, its controller chooses which defending player or which planeswalker a defending player controls it's attacking as it enters the battlefield (unless the effect that put it onto the battlefield specifies what it's attacking). Such creatures are "attacking" but, for the purposes of trigger events and effects, they never "attacked." [CompRules 2009/07/08]
• 508.6 - If no creatures are declared as attackers or put onto the battlefield attacking, skip the declare blockers and combat damage steps. [CompRules 2009/07/08]