Maddening Idol of Kozilek

Metalcraft —
{t}: Add one mana of any color. Activate only if you control three or more artifacts.

"Oh, great Kozilek, In the depths of madness I seek your truth. May your hunger burn within me as I surrender to the infinite abyss of your power. Fill me with your terrible light and guide me on the paths of the uncomprehended." —Unknown Cultist

(Mox Opal)