Commander's Plate
Artifact — Equipment
Equipped creature gets +3/+3 and has protection from each color that's not in your commander's color identity.
Equip commander 
Equip 
Not all beautiful things are fragile.
Volkan Baǵa
Commander Legends Promos (PCMR)
• #305pRulings
If your commander is a card that has no colors in its color identity, Commander's Plate gives it protection from all colors.
(wotc • 2020-11-10)
If you have two commanders and attach Commander's Plate to one, it has protection from each color not in your two commanders' combined color identity.
(wotc • 2020-11-10)
If you have no commander, Commander's Plate grants no protection abilities. The equipped creature still gets +3/+3.
(wotc • 2020-11-10)
Rulings
If your commander is a card that has no colors in its color identity, Commander's Plate gives it protection from all colors.
(wotc • 2020-11-10)
If you have two commanders and attach Commander's Plate to one, it has protection from each color not in your two commanders' combined color identity.
(wotc • 2020-11-10)
If you have no commander, Commander's Plate grants no protection abilities. The equipped creature still gets +3/+3.
(wotc • 2020-11-10)