Every distinct wording since 2010, newest first.
April 22, 2021 · Strixhaven
Mutate appears on some creature cards. It represents a static ability that functions while the spell with mutate is on the stack. “Mutate [cost]” means “You may pay [cost] rather than pay this spell’s mana cost. If you do, it becomes a mutating creature spell and targets a non-Human creature with the same owner as this spell.” Casting a spell using its mutate ability follows the rules for paying alternative costs (see 601.2b and 601.2f–h).
November 20, 2020 · Commander Legends
Encore is an activated ability that functions while the card with encore is in a graveyard. “Encore [cost]” means “[Cost], Exile this card from your graveyard: For each opponent, create a token that’s a copy of this card that attacks that opponent this turn if able. The tokens gain haste. Sacrifice them at the beginning of the next end step. Activate this ability only any time you could cast a sorcery.”