Oracle

Enchantment - Aura 

Enchant creature
Enchanted creature can't attack unless its controller pays 3.

Tournooi-info

Legal in: Vintage, Legacy, Commander

Officiele rulings

10/4/2004
This ability is paid for during the declare attackers step of the combat phase.

10/4/2004
If there are multiple combat phases during the turn, the attack cost must be paid each time if you want to attack with the creature.

10/4/2004
Paying this cost is not an instant or any other kind of ability, it is an additional cost on the declaration of the attacker.

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