La créature équipée gagne +3/+2.
À chaque fois que la créature équipée inflige des blessures de combat à un joueur, piochez une carte, puis vous pouvez lancer un sort depuis votre main avec une valeur de mana inférieure ou égale à ce nombre de blessures sans payer son coût de mana.
Équipement

You choose whether to cast a spell from among the cards in your hand as Buster Sword's middle ability resolves. You can't wait to cast one later in the turn. Timing restrictions based on the card's types are ignored.
If a spell you cast has
in its mana cost, you must choose 0 as the value of X when casting it without paying its mana cost.
If you cast a spell "without paying its mana cost," you can't choose to cast it for any alternative costs. You can, however, pay additional costs, such as kicker costs. If the card has any mandatory additional costs, those must be paid to cast the spell.