火山の奔流
ソーサリー
続唱（あなたがこの呪文を唱えたとき、コストがこれより低く土地でないカード１枚が追放されるまで、あなたのライブラリーの一番上から１枚ずつ追放していく。それをマナ・コストを支払うことなく唱えてもよい。それらの追放したカードを、無作為の順番で一番下に置く。）
火山の奔流は、対戦相手がコントロールしている、各クリーチャーと各プレインズウォーカーにそれぞれＸ点のダメージを与える。Ｘはこのターンにあなたが唱えた呪文の数に等しい。
イラスト：
Outlaws of Thunder Junction Commander#184アンコモン日本語適正
裁定
The value of X is calculated as Volcanic Torrent resolves. It will include Volcanic Torrent, spells you cast in response to Volcanic Torrent, and spells you cast prior to casting Volcanic Torrent, even if those spells haven’t resolved yet. For example, say the first spell you cast in a turn has cascade and that cascade ability causes you to cast Volcanic Torrent. Then Volcanic Torrent’s cascade ability causes you to cast another spell. When Volcanic Torrent resolves, X will be 3.
If you copy a spell, Volcanic Torrent won’t count the copy. However, if an effect instructs you to copy a card and then cast the copy, it will be counted by Volcanic Torrent.
The cascade ability triggers when you cast the spell, meaning that it resolves before that spell. If you cast the card exiled by the cascade ability, that spell will go on the stack above the spell with cascade.
When the cascade ability resolves, you must exile cards. The only optional part of the ability is whether or not you cast the last card exiled.
Countering the spell with cascade has no effect on the cascade ability.
You exile the cards face up. All players will be able to see them.
You don’t have to cast the last card exiled by a cascade ability. If you choose to do so, you’re casting it as a spell. This means that it can be countered, and appropriate abilities trigger (such as if that spell also has cascade).
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. If the card has any mandatory additional costs, you must pay those to cast the spell.
If the card has 
in its mana cost, you must choose 0 as the value of X when casting it without paying its mana cost.
The converted mana cost of a spell with cascade is determined only by its mana cost, no matter what the total cost to cast the spell was.