Rulings

• 2016-11-08
  Spells you cast from your hand this turn will gain cascade even if Yidris leaves the battlefield.
• 2016-11-08
  If Yidris’s triggered ability resolves more than once in one turn, spells you cast from your hand will gain cascade that many times. Each instance of cascade triggers separately; resolve one cascade trigger and the spell you cast from it before resolving the next cascade trigger.
• 2016-11-08
  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.
• 2016-11-08
  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.
• 2016-11-08
  If a spell with cascade is countered, the cascade ability will still resolve normally.
• 2016-11-08
  You exile the cards face up. All players will be able to see them.
• 2016-11-08
  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. It can be countered. Since it’s cast from exile, Ydris’s ability won’t give the new spell cascade.
• 2021-06-18
  The mana value of a split card is determined by the combined mana cost of its two halves. If cascade allows you to cast a split card, you may cast either half but not both halves.
• 2021-06-18
  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.
• 2021-06-18
  Due to a recent rules change to cascade, not only do you stop exiling cards if you exile a nonland card with lesser mana value than the spell with cascade, but the resulting spell you cast must also have lesser mana value. Previously, in cases where a card's mana value differed from the resulting spell, such as with some modal double-faced cards or cards with an Adventure, you could cast a spell with a higher mana value than the exiled card.
• 2021-06-18
  A spell's mana value is determined only by its mana cost. Ignore any alternative costs, additional costs, cost increases, or cost reductions.
• 2021-06-18
  Cascade triggers when you cast the spell, meaning that it resolves before that spell. If you end up casting the exiled card, it will go on the stack above the spell with cascade.
• 2021-06-18
  If you cast a card “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 card.
• 2016-11-08
  If Yidris's triggered ability resolves more than once in one turn, spells you cast from your hand will gain cascade that many times. Each instance of cascade triggers separately; resolve one cascade trigger and the spell you cast from it before resolving the next cascade trigger.
• 2021-06-18
  Due to a 2021 rules change to cascade, not only do you stop exiling cards if you exile a nonland card with lesser mana value than the spell with cascade, but the resulting spell you cast must also have lesser mana value. Previously, in cases where a card's mana value differed from the resulting spell, such as with some modal double-faced cards or cards with an Adventure, you could cast a spell with a higher mana value than the exiled card.
• 2021-06-18
  If you cast a card "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 card.