鉄頭のアーニ

あなたがコントロールしているクリーチャー１体が攻撃するか、クリーチャー１体があなたのコントロール下で攻撃している状態で戦場に出るたび、あなたは{1}{R}を支払ってもよい。そうしたなら、あなたの手札にありマナ総量がそのクリーチャーのマナ総量より少ないクリーチャー・カード１枚をタップ状態かつ攻撃している状態で戦場に出してもよい。

钢角亚尼

每当一个由你操控的生物攻击或一个生物以正进行攻击之状态在你的操控下进战场时，你可以支付{1}{R}。若你如此作，则你可以将一张法术力值小于该生物的生物牌从你手上横置放进战场，且正进行攻击。

Arni Metalbrow

Whenever a creature you control attacks or a creature you control enters attacking, you may pay {1}{R}. If you do, you may put a creature card with mana value less than that creature's mana value from your hand onto the battlefield tapped and attacking.

March of the Machine: The Aftermath

Whenever a creature you control attacks or a creature enters the battlefield under your control attacking, you may pay {1}{R}. If you do, you may put a creature card with mana value less than that creature's mana value from your hand onto the battlefield tapped and attacking.

If the attacking creature or creature that entered the battlefield attacking isn't on the battlefield as the triggered ability resolves, use its mana value from when it was last on the battlefield. (If it's on the battlefield but is no longer attacking, use its current mana value.)

Putting a creature onto the battlefield attacking as the ability resolves will cause the ability to trigger again. This instance of the ability will consider the mana value of the new creature that entered the battlefield attacking.

You decide whether to pay {1}{R} as the triggered ability resolves.