■ Ninja Strike 4 (Whenever one of your opponent 's creatures attacks or blocks , if you have 4 or more cards in your mana zone and if during that attack you didn't use a " Ninja Strike " ability , you may summon this Shinobi for no cost . At the end of that turn , put this Shinobi on the bottom of your deck .)

■ When you put this creature , your opponent chooses a card in their hand and discards it.