Promise of Loyalty
Sorcery{4}{W}
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.
Colour identity White
In short
Promise of Loyalty has 13 listed printings; the most valuable is the Surge Foil printing from FIC at US$5.41 on TCGplayer's market price. Prices below are the cheapest in-stock listing in the United States.
Every Promise of Loyalty printing
Surge Foil
Promise of Loyalty
FIC · 249
TCGplayer market
US$5.41
Extended Art
Promise of Loyalty
C21 · 348
Price not tracked
Extended Art
Promise of Loyalty
MSC · 319
Price not tracked
Promise of Loyalty
C21 · 21
Price not tracked
Surge Foil
Promise of Loyalty
MSC · 142
Price not tracked
Promise of Loyalty
MOC · 200
Price not tracked
Promise of Loyalty
CMM · 833
Price not tracked
Promise of Loyalty
FIC · 249
Price not tracked
Promise of Loyalty
MKC · 79
Price not tracked
Promise of Loyalty
BLC · 148
Price not tracked
Promise of Loyalty
MSC · 142
Price not tracked
Promise of Loyalty
SOC · 161
Price not tracked
The List
Promise of Loyalty
PLST · BLC-148
TCGplayer market
US$0.19