Mountain

Aven Fisher

Flying (This creature can't be blocked except by creatures with flying or reach.)
When this creature dies, you may draw a card.

Scalpelexis

Flying (This creature can't be blocked except by creatures with flying or reach.)
Whenever this creature deals combat damage to a player, that player exiles the top four cards of their library. If two or more of those cards have the same name, repeat this process.

Skywing Aven

Flying
Discard a card: Return this creature to its owner's hand.

Barbarian Bully

Discard a card at random: This creature gets +2/+2 until end of turn unless a player has this creature deal 4 damage to them. Activate only once each turn.

Concentrate

Violent Eruption

Violent Eruption deals 4 damage divided as you choose among any number of targets.
Madness {1}{R}{R} (If you discard this card, discard it into exile. When you do, cast it for its madness cost or put it into your graveyard.)

Wonder

Flying
As long as this card is in your graveyard and you control an Island, creatures you control have flying.

Flash of Insight

Look at the top X cards of your library. Put one of them into your hand and the rest on the bottom of your library in any order.
Flashback—{1}{U}, Exile X blue cards from your graveyard. (You may cast this card from your graveyard for its flashback cost, then exile it. You can't exile Flash of Insight to pay for its own flashback cost.)

Fiery Temper

Fiery Temper deals 3 damage to any target.
Madness {R} (If you discard this card, discard it into exile. When you do, cast it for its madness cost or put it into your graveyard.)

Wormfang Turtle

When this creature enters, exile a land you control.
When this creature leaves the battlefield, return the exiled card to the battlefield under its owner's control.

Dwarven Scorcher

Sacrifice this creature: This creature deals 1 damage to target creature unless that creature's controller has this creature deal 2 damage to them.

Aven Windreader

Flying (This creature can't be blocked except by creatures with flying or reach.)
{1}{U}: Target player reveals the top card of their library.

Hapless Researcher

Sacrifice this creature: Draw a card, then discard a card.

Compulsion

{1}{U}, Discard a card: Draw a card.
{1}{U}, Sacrifice this enchantment: Draw a card.

Island

Shivan Dragon

Flying
{R}: This creature gets +1/+0 until end of turn.

Churning Eddy

Return target creature and target land to their owners' hands.

Swelter

Swelter deals 2 damage to each of two target creatures.

Lava Dart

Lava Dart deals 1 damage to any target.
Flashback—Sacrifice a Mountain. (You may cast this card from your graveyard for its flashback cost. Then exile it.)

Chainflinger

{1}{R}, {T}: This creature deals 1 damage to any target.
Threshold — {2}{R}, {T}: This creature deals 2 damage to any target. Activate only if seven or more cards are in your graveyard.

Barbarian Lunatic

{2}{R}, Sacrifice this creature: It deals 2 damage to target creature.

Shower of Coals

Shower of Coals deals 2 damage to each of up to three targets.
Threshold — Shower of Coals deals 4 damage to each of those permanents and/or players instead if seven or more cards are in your graveyard.