Ravnica, City of Guilds

{t} add {w},{u},{b},{r}, or {g} to your mana pool
{t}sacrifice two artifacts, creatures,
or enchantments, add two {w},{u},{b},{r}, or {g}
for any {w},{u},{b},{r}, or {g} in it's cost
{t}destroy one land for each color, and then
sacrifice Ravnica, City of Guilds and destroy all
mono colored or triple colored permanents