Winternight Stories

Draw three cards. Then discard two cards unless you discard a creature card.
Harmonize {4}{U} (You may cast this card from your graveyard for its harmonize cost. You may tap a creature you control to reduce that cost by {X}, where X is its power. Then exile this spell.)

Herd Heirloom

{T}: Add one mana of any color. Spend this mana only to cast a creature spell.
{T}: Until end of turn, target creature you control with power 4 or greater gains trample and "Whenever this creature deals combat damage to a player, draw a card."

Ureni, the Song Unending

Flying, protection from white and from black
When Ureni enters, it deals X damage divided as you choose among any number of target creatures and/or planeswalkers your opponents control, where X is the number of lands you control.

Sarkhan, Dragon Ascendant

When Sarkhan enters, you may behold a Dragon. If you do, create a Treasure token. (To behold a Dragon, choose a Dragon you control or reveal a Dragon card from your hand.)
Whenever a Dragon you control enters, put a +1/+1 counter on Sarkhan. Until end of turn, Sarkhan becomes a Dragon in addition to its other types and gains flying.

Roiling Dragonstorm

When this enchantment enters, draw two cards, then discard a card.
When a Dragon you control enters, return this enchantment to its owner's hand.

Frontier Bivouac

This land enters tapped.
{T}: Add {G}, {U}, or {R}.

Thornwood Falls

This land enters tapped.
When this land enters, you gain 1 life.
{T}: Add {G} or {U}.

Forest

Dragonologist

When this creature enters, look at the top six cards of your library. You may reveal an instant, sorcery, or Dragon card from among them and put it into your hand. Put the rest on the bottom of your library in a random order.
Untapped Dragons you control have hexproof.

Maelstrom of the Spirit Dragon

{T}: Add {C}.
{T}: Add one mana of any color. Spend this mana only to cast a Dragon spell or an Omen spell.
{4}, {T}, Sacrifice this land: Search your library for a Dragon card, reveal it, put it into your hand, then shuffle.

Dragonstorm Globe

Each Dragon you control enters with an additional +1/+1 counter on it.
{T}: Add one mana of any color.

Roost Seek

Search your library for a basic land card, reveal it, put it into your hand, then shuffle. (Also shuffle this card.)

Sagu Wildling

Flying
When this creature enters, you gain 3 life.

Sagu Wildling // Roost Seek

Island

Coil and Catch

Draw three cards, then discard a card. (Then shuffle this card into its owner's library.)

Marang River Regent

Flying
When this creature enters, return up to two other target nonland permanents to their owners' hands.

Marang River Regent // Coil and Catch

Molten Exhale

You may cast this spell as though it had flash if you behold a Dragon as an additional cost to cast it. (To behold a Dragon, choose a Dragon you control or reveal a Dragon card from your hand.)
Molten Exhale deals 4 damage to target creature or planeswalker.

Encroaching Dragonstorm

When this enchantment enters, search your library for up to two basic land cards, put them onto the battlefield tapped, then shuffle.
When a Dragon you control enters, return this enchantment to its owner's hand.

Piercing Exhale

As an additional cost to cast this spell, you may behold a Dragon. (You may choose a Dragon you control or reveal a Dragon card from your hand.)
Target creature you control deals damage equal to its power to target creature or planeswalker. If a Dragon was beheld, surveil 2.

Mountain

Rugged Highlands

This land enters tapped.
When this land enters, you gain 1 life.
{T}: Add {R} or {G}.