While resolving Valefor's first chapter ability, the next opponent in turn order chooses a creature with the greatest mana value among creatures they control, then each other opponent in turn order does the same. Then the chosen creatures are returned to their owners' hands simultaneously.
2025-06-06 • wotc
If a creature on the battlefield has {X} in its mana cost, X is 0 for the purpose of determining its mana value.
2025-06-06 • wotc