Promise of Loyalty

Mana cost: {4}{W}
Type: Sorcery
Set: Commander 2021 #348 (rare)
Price: $2.69 USD

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.

Promise of Loyalty has 14 printings, first in Commander 2021 (2021). EDHREC ranks it #925 among Commander cards. It appears most in Ms. Bumbleflower decks (17,363 on EDHREC). 10 public decks on TCG run it. It has 3 official rulings.

Legality

commander: legal
legacy: legal
vintage: legal
pauper: not legal
modern: not legal
pioneer: not legal
standard: not legal
brawl: not legal

Public decks that run Promise of Loyalty

Blame Game - Murders at Karlov Manor Commander, led by Nelly Borca, Impulsive Accuser
Cavalry Charge - March of the Machine Commander, led by Sidar Jabari of Zhalfir
Counter Blitz - Final Fantasy Commander, led by Tidus, Yuna's Guardian
Federation Fleet - Star Trek Commander, led by Jean-Luc Picard, Luminary
Odds and Ends - Secret Lair Commander, led by Yennett, Cryptic Sovereign
Peace Offering - Bloomburrow Commander, led by Ms. Bumbleflower
Planeswalker Party - Commander Masters, led by Commodore Guff
Silverquill Influence - Secrets of Strixhaven, led by Killian, Decisive Mentor
Silverquill Statement - Commander 2021, led by Breena, the Demagogue
The Fantastic Four - Marvel Super Heroes, led by Mister Fantastic

Commanders that run Promise of Loyalty most

Deck counts from EDHREC.

Ms. Bumbleflower: 17,363 decks
Y'shtola, Night's Blessed: 7,913 decks
Tidus, Yuna's Guardian: 7,569 decks
Killian, Decisive Mentor: 6,407 decks
Queen Marchesa: 6,269 decks
Nelly Borca, Impulsive Accuser: 4,777 decks
Sidar Jabari of Zhalfir: 4,473 decks
Breena, the Demagogue: 4,420 decks

Often played with Promise of Loyalty

Cards that show up in the same decks on EDHREC.

Rulings

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