2021-04-16 : 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.

2021-04-16 : If the vow counter is moved to another creature, it won't prevent the second creature from attacking normally.

2021-04-16 : If the vow counter is removed from the creature, it can attack as normal.