Tranquil Frillback

When Tranquil Frillback enters, you may pay {G} up to three times. When you pay this cost one or more times, choose up to that many —
• Destroy target artifact or enchantment.
• Exile target player's graveyard.
• You gain 4 life.

Cavernous Maw

{T}: Add {C}.
{2}: Cavernous Maw becomes a 3/3 Elemental creature until end of turn. It's still a Cave land. Activate only if the number of other Caves you control plus the number of Cave cards in your graveyard is three or greater.

Echoing Deeps

You may have Echoing Deeps enter tapped as a copy of any land card in a graveyard, except it's a Cave in addition to its other types.
{T}: Add {C}.

Sunken Citadel

Sunken Citadel enters tapped. As it enters, choose a color.
{T}: Add one mana of the chosen color.
{T}: Add two mana of the chosen color. Spend this mana only to activate abilities of land sources.

Bushwhack

Choose one —
• Search your library for a basic land card, reveal it, put it into your hand, then shuffle.
• Target creature you control fights target creature you don't control. (Each deals damage equal to its power to the other.)

Nissa, Ascended Animist

Compleated ({G/P} can be paid with {G} or 2 life. For each {G/P} paid with life, this planeswalker enters with two fewer loyalty counters.)
+1: Create an X/X green Phyrexian Horror creature token, where X is Nissa, Ascended Animist's loyalty.
−1: Destroy target artifact or enchantment.
−7: Until end of turn, creatures you control get +1/+1 for each Forest you control and gain trample.

Heaped Harvest

When Heaped Harvest enters and when you sacrifice it, you may search your library for a basic land card, put it onto the battlefield tapped, then shuffle.
{2}, {T}, Sacrifice Heaped Harvest: You gain 3 life.

Vaultborn Tyrant

Trample
Whenever Vaultborn Tyrant or another creature you control with power 4 or greater enters, you gain 3 life and draw a card.
When Vaultborn Tyrant dies, if it's not a token, create a token that's a copy of it, except it's an artifact in addition to its other types.

Pit of Offerings

Pit of Offerings enters tapped.
When Pit of Offerings enters, exile up to three target cards from graveyards.
{T}: Add {C}.
{T}: Add one mana of any of the exiled cards' colors.

Cosmium Confluence

Choose three. You may choose the same mode more than once.
• Search your library for a Cave card, put it onto the battlefield tapped, then shuffle.
• Put three +1/+1 counters on a Cave you control. It becomes a 0/0 Elemental creature with haste. It's still a land.
• Destroy target enchantment.

Tyrranax Rex

This spell can't be countered.
Trample, ward {4}, haste
Toxic 4 (Players dealt combat damage by this creature also get four poison counters.)

Forest

Up the Beanstalk

When Up the Beanstalk enters and whenever you cast a spell with mana value 5 or greater, draw a card.

Cityscape Leveler

Trample
When you cast this spell and whenever Cityscape Leveler attacks, destroy up to one target nonland permanent. Its controller creates a tapped Powerstone token.
Unearth {8}

Spelunking

When Spelunking enters, draw a card, then you may put a land card from your hand onto the battlefield. If you put a Cave onto the battlefield this way, you gain 4 life.
Lands you control enter untapped.

Glimpse the Core

Choose one —
• Search your library for a basic Forest card, put that card onto the battlefield tapped, then shuffle.
• Return target Cave card from your graveyard to the battlefield tapped.

The Filigree Sylex

{T}: Put an oil counter on The Filigree Sylex.
{T}, Sacrifice The Filigree Sylex: Destroy each nonland permanent with mana value equal to the number of oil counters on The Filigree Sylex.
{T}, Remove ten oil counters from among permanents you control and sacrifice The Filigree Sylex: It deals 10 damage to any target.

Pick Your Poison

Choose one —
• Each opponent sacrifices an artifact.
• Each opponent sacrifices an enchantment.
• Each opponent sacrifices a creature with flying.

Obstinate Baloth

When Obstinate Baloth enters, you gain 4 life.
If a spell or ability an opponent controls causes you to discard Obstinate Baloth, put it onto the battlefield instead of putting it into your graveyard.

Fountainport

{T}: Add {C}.
{2}, {T}, Sacrifice a token: Draw a card.
{3}, {T}, Pay 1 life: Create a 1/1 blue Fish creature token.
{4}, {T}: Create a Treasure token.

Archdruid's Charm

Choose one —
• Search your library for a creature or land card and reveal it. Put it onto the battlefield tapped if it's a land card. Otherwise, put it into your hand. Then shuffle.
• Put a +1/+1 counter on target creature you control. It deals damage equal to its power to target creature you don't control.
• Exile target artifact or enchantment.

Hidden Nursery

Hidden Nursery enters tapped.
{T}: Add {G}.
{4}{G}, {T}, Sacrifice Hidden Nursery: Discover 4. Activate only as a sorcery. (Exile cards from the top of your library until you exile a nonland card with mana value 4 or less. Cast it without paying its mana cost or put it into your hand. Put the rest on the bottom in a random order.)

Argoth, Sanctum of Nature

Argoth, Sanctum of Nature enters tapped unless you control a legendary green creature.
{T}: Add {G}.
{2}{G}{G}, {T}: Create a 2/2 green Bear creature token, then mill three cards. Activate only as a sorcery.
(Melds with Titania, Voice of Gaea.)