エメリアの盾、イオナ

飛行
エメリアの盾、イオナが戦場に出るに際し、色を１色選ぶ。
あなたの対戦相手は選ばれた色の呪文を唱えられない。

伊美黎之盾艾欧娜

飞行
于伊美黎之盾艾欧娜进战场时，选择一种颜色。
所有对手都不能施放该色的咒语。

Iona, Shield of Emeria

Flying
As Iona enters, choose a color.
Your opponents can't cast spells of the chosen color.

Mystery Booster 2

Flying
As Iona, Shield of Emeria enters the battlefield, choose a color.
Your opponents can't cast spells of the chosen color.

From the Vault: Angels

Modern Masters 2015

Zendikar

Iona's third ability includes permanent spells (artifacts, creatures, enchantments, and planeswalkers), not just instant and sorcery spells. It does not include lands or abilities (such as cycling or unearth).

Once the color is chosen, it's too late for opponents to respond by casting spells of that color. Iona is not yet in the battlefield at the time the color is chosen, so, for example, there's no way for an opponent to destroy it by casting Doom Blade if the chosen color is black.