Command Tower

{T}: Add one mana of any color in your commander's color identity.

Plains

Forest

Garth One-Eye

{T}: Choose a card name that hasn't been chosen from among Disenchant, Braingeyser, Terror, Shivan Dragon, Regrowth, and Black Lotus. Create a copy of the card with the chosen name. You may cast the copy. (You still pay its costs.)

Island

Swamp

Exotic Orchard

{T}: Add one mana of any color that a land an opponent controls could produce.

Mountain

Reliquary Tower

You have no maximum hand size.
{T}: Add {C}.

Tundra

The World Tree

The World Tree 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 The World Tree: Search your library for any number of God cards, put them onto the battlefield, then shuffle.