Sky Blue Sky

As long as Sky Blue Sky is on the battlefield all colored mana symbols (including hybrid and phyrexian) on all cards in this game are replaced with (1).
(12): All opponents must agree to activate this ability by paying it's mana cost together. Multiple opponents must pay for it at a minimum of (1) per person. Exile or destroy Sky Blue Sky.
I regret this, men. I regret it deeply. It must be done.