Nissa, Sage Animist

+1: Reveal the top card of your library. If it's a land card, put it onto the battlefield. Otherwise, put it into your hand.
−2: Create Ashaya, the Awoken World, a legendary 4/4 green Elemental creature token.
−7: Untap up to six target lands. They become 6/6 Elemental creatures. They're still lands.

Nissa, Vastwood Seer

When Nissa, Vastwood Seer enters, you may search your library for a basic Forest card, reveal it, put it into your hand, then shuffle.
Whenever a land you control enters, if you control seven or more lands, exile Nissa, then return her to the battlefield transformed under her owner's control.

Nissa, Vastwood Seer // Nissa, Sage Animist

Gaea's Cradle

{T}: Add {G} for each creature you control.

Flagstones of Trokair

{T}: Add {W}.
When Flagstones of Trokair is put into a graveyard from the battlefield, you may search your library for a Plains card, put it onto the battlefield tapped, then shuffle.

Geier Reach Sanitarium

{T}: Add {C}.
{2}, {T}: Each player draws a card, then discards a card.

Nykthos, Shrine to Nyx

{T}: Add {C}.
{2}, {T}: Choose a color. Add an amount of mana of that color equal to your devotion to that color. (Your devotion to a color is the number of mana symbols of that color in the mana costs of permanents you control.)

Boseiju, Who Shelters All

Boseiju, Who Shelters All enters tapped.
{T}, Pay 2 life: Add {C}. If that mana is spent on an instant or sorcery spell, that spell can't be countered.

Azusa, Lost but Seeking

You may play two additional lands on each of your turns.

Serra's Sanctum

{T}: Add {W} for each enchantment you control.

Yavimaya, Cradle of Growth

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

Okina, Temple to the Grandfathers

{T}: Add {G}.
{G}, {T}: Target legendary creature gets +1/+1 until end of turn.

Gemstone Caverns

If Gemstone Caverns is in your opening hand and you're not the starting player, you may begin the game with Gemstone Caverns on the battlefield with a luck counter on it. If you do, exile a card from your hand.
{T}: Add {C}. If Gemstone Caverns has a luck counter on it, instead add one mana of any color.

Ashaya, Soul of the Wild

Ashaya, Soul of the Wild's power and toughness are each equal to the number of lands you control.
Nontoken creatures you control are Forest lands in addition to their other types. (They're still affected by summoning sickness.)

Pendelhaven

{T}: Add {G}.
{T}: Target 1/1 creature gets +1/+2 until end of turn.

Eiganjo Castle

{T}: Add {W}.
{W}, {T}: Prevent the next 2 damage that would be dealt to target legendary creature this turn.

Miren, the Moaning Well

{T}: Add {C}.
{3}, {T}, Sacrifice a creature: You gain life equal to the sacrificed creature's toughness.

Yavimaya Hollow

{T}: Add {C}.
{G}, {T}: Regenerate target creature.

Hall of Heliod's Generosity

{T}: Add {C}.
{1}{W}, {T}: Put target enchantment card from your graveyard on top of your library.

Captain Sisay

{T}: Search your library for a legendary card, reveal that card, put it into your hand, then shuffle.