The World Tree (KHM #275)

This land enters tapped.

{T}: Add {G}.

As long as you control six or more lands, lands you control have “{T}: Add one mana of any color.”

{W}{W}{U}{U}{B}{B}{R}{R}{G}{G}, {T}, Sacrifice this land: Search your library for any number of God cards, put them onto the battlefield, then shuffle.