Rulings
If your commander is a card that has no colors in its color identity, Arcane Signet's ability produces no mana. It doesn't produce {C}.
If you don't have a commander, Arcane Signet's ability produces no mana.
If you have two commanders, the ability adds one mana of any color in their combined color identities.
Legality
- TLR
- Duel
- Brawl
- Penny
- PreDH
- Future
- Legacy
- Modern
- Pauper
- Alchemy
- Pioneer
- Vintage
- Historic
- Standard
- Timeless
- Commander
- Gladiator
- Old School
- Premodern
- Oathbreaker
- Standard Brawl
- Pauper Commander
- Competitive Brawl
Often played with
-
Sol Ring
×0 -
Solemn Simulacrum
×0 -
Black Market Connections
×0 -
Damnation
×0 -
Lightning Greaves
×0 -
Phyrexian Arena
×0 -
The Meathook Massacre
×0 -
Thran Dynamo
×0 -
Archon of Cruelty
×0 -
Black Market
×0