Rulings

• 2011-09-22
  The color identity of your commander is set before the game begins and doesn’t change during the game, even your commander is in a hidden zone (like the hand or library) or an effect changes your commander’s color.
• 2011-09-22
  If your commander is a card like Kozilek, Butcher of Truth that has no colors in its color identity, Command Tower’s ability produces no mana.
• 2011-09-22
  In formats other than Commander, Command Tower’s ability produces no mana.
• 2019-10-04
  If you don’t have a commander, Command Tower’s ability produces no mana.
• 2019-10-04
  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 .
• 2019-10-04
  The color identity of your commander is set before the game begins and doesn’t change during the game, even if your commander is in a hidden zone (like the hand or library) or an effect changes your commander’s color.
• 2020-11-10
  If you have two commanders, the ability adds one mana of any color in their combined color identities.
• 2020-11-10
  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 .
• 2020-11-10
  If you don't have a commander, Command Tower's ability produces no mana.