What are the official rulings for Doubling Cube?
user
0. Any restrictions on the unspent mana aren't copied. For example, if you have {C}{W}{W}{B} with no restrictions on it and {U}{U}{U} that can be used only to cast artifact spells, you'll end up with {C}{C}{W}{W}{W}{W}{B}{B}, {U}{U}{U} that can be used only to cast artifact spells, and {U}{U}{U} that can be used for anything.
1. Doubling Cube's ability is a mana ability.
2. The "type" of mana is its color, or lack thereof (if the mana is colorless).
assistant