Historical Rules · 16 January 2026
Rule 709.5e
Official source text from the 16 January 2026 Rules release
A player who controls a permanent that has one or more locked halves may pay the mana cost of a locked half of that permanent to give that permanent the appropriate unlocked designation. This cost is referred to as an “unlock cost.” This is a special action (see rule 116). A player can take this action any time they have priority and the stack is empty during a main phase of their turn.