Command Tower
Land
: Add one mana of any color in your commander's color identity.
Safe havens amid the desert and dragonstorms, Abzan fortresses attract merchants, travelers, outcasts, and exiles.
Illustrated by
Tarkir: Dragonstorm Commander#107CommonEnglishLegality
Rulings
Nov 10, 2020
If you have two commanders, the ability adds one mana of any color in their combined color identities.
Nov 10, 2020
If your commander is a card that has no colors in its color identity, Command Tower's ability produces no mana. It doesn't produce 
.
Nov 10, 2020
If you don't have a commander, Command Tower's ability produces no mana.