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.

Faceless Haven

{T}: Add {C}.
{S}{S}{S}: Faceless Haven becomes a 4/3 creature with vigilance and all creature types until end of turn. It's still a land. ({S} can be paid with one mana from a snow source.)

Glacial Floodplain

({T}: Add {W} or {U}.)
Glacial Floodplain enters tapped.

Swarmyard

{T}: Add {C}.
{T}: Regenerate target Insect, Rat, Spider, or Squirrel. (The next time it would be destroyed this turn, instead tap it, remove it from combat, and heal all damage on it.)

Exotic Orchard

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

Arctic Treeline

({T}: Add {G} or {W}.)
Arctic Treeline enters tapped.

Sulfurous Mire

({T}: Add {B} or {R}.)
Sulfurous Mire enters tapped.

Dark Depths

Dark Depths enters with ten ice counters on it.
{3}: Remove an ice counter from Dark Depths.
When Dark Depths has no ice counters on it, sacrifice it. If you do, create Marit Lage, a legendary 20/20 black Avatar creature token with flying and indestructible.

Snow-Covered Mountain

Urborg, Tomb of Yawgmoth

Each land is a Swamp in addition to its other land types.

Ice Tunnel

({T}: Add {U} or {B}.)
Ice Tunnel enters tapped.

Thespian's Stage

{T}: Add {C}.
{2}, {T}: Thespian's Stage becomes a copy of target land, except it has this ability.

Highland Forest

({T}: Add {R} or {G}.)
Highland Forest enters tapped.

Morophon, the Boundless

Changeling (This card is every creature type.)
As Morophon, the Boundless enters, choose a creature type.
Spells of the chosen type you cast cost {W}{U}{B}{R}{G} less to cast. This effect reduces only the amount of colored mana you pay.
Other creatures you control of the chosen type get +1/+1.

Snow-Covered Plains

Mutavault

{T}: Add {C}.
{1}: Mutavault becomes a 2/2 creature with all creature types until end of turn. It's still a land.

Alpine Meadow

({T}: Add {R} or {W}.)
Alpine Meadow enters tapped.

Path of Ancestry

Path of Ancestry enters tapped.
{T}: Add one mana of any color in your commander's color identity. When that mana is spent to cast a creature spell that shares a creature type with your commander, scry 1. (Look at the top card of your library. You may put that card on the bottom.)

Volatile Fjord

({T}: Add {U} or {R}.)
Volatile Fjord enters tapped.

Reliquary Tower

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

Yavimaya, Cradle of Growth

Each land is a Forest in addition to its other land types.

Woodland Chasm

({T}: Add {B} or {G}.)
Woodland Chasm enters tapped.

Command Tower

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

Snowfield Sinkhole

({T}: Add {W} or {B}.)
Snowfield Sinkhole enters tapped.