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Each player puts a vow counter on a creature they control and sacrifices the rest. Each of those creatures can't attack you or planeswalkers you control for as long as it has a vow counter on it.
Each player, including you, must put a vow counter on a creature they control if able. They can't choose to opt out and sacrifice all of their creatures. The creature you put a vow counter on will remember its promise if another player gains control of it.
If the vow counter is moved to another creature, it won't prevent the second creature from attacking normally.
If the vow counter is removed from the creature, it can attack as normal.
