Mountain

Turbulent Dreams

As an additional cost to cast this spell, discard X cards.
Return X target nonland permanents to their owners' hands.

Shattered Perception

Discard all the cards in your hand, then draw that many cards.
Flashback {5}{R} (You may cast this card from your graveyard for its flashback cost. Then exile it.)

Laboratory Maniac

If you would draw a card while your library has no cards in it, you win the game instead.

Displacer Kitten

Avoidance — Whenever you cast a noncreature spell, exile up to one target nonland permanent you control, then return that card to the battlefield under its owner's control.

Rewind

Counter target spell. Untap up to four lands.

Rielle, the Everwise

Rielle, the Everwise gets +1/+0 for each instant and sorcery card in your graveyard.
Whenever you discard one or more cards for the first time each turn, draw that many cards.

Snap

Return target creature to its owner's hand. Untap up to two lands.

Tolarian Winds

Discard all the cards in your hand, then draw that many cards.

Anje's Ravager

Anje's Ravager attacks each combat if able.
Whenever Anje's Ravager attacks, discard your hand, then draw three cards.
Madness {1}{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.)

Devastating Dreams

As an additional cost to cast this spell, discard X cards at random.
Each player sacrifices X lands of their choice. Devastating Dreams deals X damage to each creature.

Breakthrough

Draw four cards, then choose X cards in your hand and discard the rest.

Reforge the Soul

Each player discards their hand, then draws seven cards.
Miracle {1}{R} (You may cast this card for its miracle cost when you draw it if it's the first card you drew this turn.)

Diamond Lion

{T}, Discard your hand, Sacrifice Diamond Lion: Add three mana of any one color. Activate only as an instant.

Sulfur Falls

Sulfur Falls enters tapped unless you control an Island or a Mountain.
{T}: Add {U} or {R}.

Planar Incision

Exile target artifact or creature, then return it to the battlefield under its owner's control with a +1/+1 counter on it.

Animate Dead

Enchant creature card in a graveyard
When Animate Dead enters, if it's on the battlefield, it loses "enchant creature card in a graveyard" and gains "enchant creature put onto the battlefield with Animate Dead." Return enchanted creature card to the battlefield under your control and attach Animate Dead to it. When Animate Dead leaves the battlefield, that creature's controller sacrifices it.
Enchanted creature gets -1/-0.

Glint-Horn Buccaneer

Haste
Whenever you discard a card, Glint-Horn Buccaneer deals 1 damage to each opponent.
{1}{R}, Discard a card: Draw a card. Activate only if Glint-Horn Buccaneer is attacking.

Summons of Saruman

Amass Orcs X. Mill X cards. You may cast an instant or sorcery spell with mana value X or less from among them without paying its mana cost. (To amass Orcs X, put X +1/+1 counters on an Army you control. It's also an Orc. If you don't control an Army, create a 0/0 black Orc Army creature token first.)
Flashback—{3}{U}{R}, Exile X cards from your graveyard.

Firestorm

As an additional cost to cast this spell, discard X cards.
Firestorm deals X damage to each of X targets.

Frantic Search

Draw two cards, then discard two cards. Untap up to three lands.

Anger

Haste
As long as Anger is in your graveyard and you control a Mountain, creatures you control have haste.

Siren's Ruse

Exile target creature you control, then return that card to the battlefield under its owner's control. If a Pirate was exiled this way, draw a card.

Island

High Tide

Until end of turn, whenever a player taps an Island for mana, that player adds an additional {U}.