Spectacle

Spectacle is a keyword ability that gives spells an alternative cost. You can cast a spell for its spectacle cost if an opponent lost life during the turn. It was introduced in Ravnica Allegiance for the Cult of Rakdos of Ravnica.

Description
On some cards, the alternative cost is a discount, a reward for hurting your opponents. For other cards, the spectacle cost is higher, but there's an additional reward for paying that cost. Paying a spectacle cost is always optional, even if an opponent lost life that turn. Even if you pay a spectacle cost, the mana cost and converted mana cost of the spell don't change.

Rulings

 * Damage dealt to a player causes that player to lose that much life.
 * Spectacle doesn't change when you can cast the card. For example, you can't cast a sorcery with spectacle during an opponent's turn unless another effect allows you to do so, even if that player has lost life this turn.
 * To determine the total cost of a spell, start with the mana cost or alternative cost you're paying (such as a spectacle cost), add any cost increases, then apply any cost reductions. The converted mana cost of the spell remains unchanged, no matter what the total cost to cast it was.
 * A card's spectacle cost is the same no matter how much life your opponents lost or how many opponents lost life.
 * In a multiplayer game, if an opponent loses life and later that turn leaves the game, you can cast a spell for its spectacle cost. (If a player leaves the game during their turn, that turn continues without an active player.)