Doubling Cube // Doubling Cube

{3}, {T}: Double the amount of each type of unspent mana you have.

"Freedom is the right of all sentient beings."
—Optimus Prime

Secret Lair Drop

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.

Doubling Cube's ability is a mana ability.

The "type" of mana is its color, or lack thereof (if the mana is colorless).