Horizon Stone

If you would lose unspent mana, that mana becomes colorless instead.

Loreseeker's Stone

{3}, {T}: Draw three cards. This ability costs {1} more to activate for each card in your hand.

Scourge of Fleets

When Scourge of Fleets enters, return each creature your opponents control with toughness X or less to its owner's hand, where X is the number of Islands you control.

Ash Barrens

{T}: Add {C}.
Basic landcycling {1} ({1}, Discard this card: Search your library for a basic land card, reveal it, put it into your hand, then shuffle.)

Urza's Power Plant

{T}: Add {C}. If you control an Urza's Mine and an Urza's Tower, add {C}{C} instead.

Millikin

{T}, Mill a card: Add {C}. (To mill a card, put the top card of your library into your graveyard.)

Cinderheart Giant

Trample
When Cinderheart Giant dies, it deals 7 damage to a creature an opponent controls chosen at random.

Mental Journey

Draw three cards.
Basic landcycling {1}{U} ({1}{U}, Discard this card: Search your library for a basic land card, reveal it, put it into your hand, then shuffle.)

Ore-Scale Guardian

This spell costs {1} less to cast for each land card in your graveyard.
Flying, haste

Citywatch Sphinx

Flying
When Citywatch Sphinx dies, surveil 2. (Look at the top two cards of your library, then put any number of them into your graveyard and the rest on top of your library in any order.)

Captivating Gyre

Return up to three target creatures to their owners' hands.

Explosive Welcome

Explosive Welcome deals 5 damage to any target and 3 damage to any other target. Add {R}{R}{R}.

Ripscale Predator

Menace (This creature can't be blocked except by two or more creatures.)

Chartooth Cougar

{R}: Chartooth Cougar gets +1/+0 until end of turn.
Mountaincycling {2} ({2}, Discard this card: Search your library for a Mountain card, reveal it, put it into your hand, then shuffle.)

Harbor Serpent

Islandwalk (This creature can't be blocked as long as defending player controls an Island.)
Harbor Serpent can't attack unless there are five or more Islands on the battlefield.

Pharagax Giant

Tribute 2 (As this creature enters, an opponent of your choice may put two +1/+1 counters on it.)
When Pharagax Giant enters, if tribute wasn't paid, Pharagax Giant deals 5 damage to each opponent.

Swirling Torrent

Choose one or both —
• Put target creature on top of its owner's library.
• Return target creature to its owner's hand.

Floodwaters

Return up to two target creatures to their owners' hands.
Cycling {2} ({2}, Discard this card: Draw a card.)

Urza's Tower

{T}: Add {C}. If you control an Urza's Mine and an Urza's Power-Plant, add {C}{C}{C} instead.

Razorfield Thresher

Volcanic Dragon

Elemental Masterpiece

Create two 4/4 blue and red Elemental creature tokens.
{U/R}{U/R}, Discard Elemental Masterpiece: Create a Treasure token. (It's an artifact with "{T}, Sacrifice this artifact: Add one mana of any color.")

Mountain

Interpret the Signs

Scry 3, then reveal the top card of your library. Draw cards equal to that card's mana value. (To scry 3, look at the top three cards of your library, then put any number of them on the bottom and the rest on top in any order.)

Sea God's Scorn

Return up to three target creatures and/or enchantments to their owners' hands.

Bone Pit Brute

Menace (This creature can't be blocked except by two or more creatures.)
When Bone Pit Brute enters, target creature gets +4/+0 until end of turn.

Gargadon

Trample
Suspend 4—{1}{R} (Rather than cast this card from your hand, you may pay {1}{R} and exile it with four time counters on it. At the beginning of your upkeep, remove a time counter. When the last is removed, you may cast it without paying its mana cost. It has haste.)

Wizard Class

(Gain the next level as a sorcery to add its ability.)
You have no maximum hand size.
{2}{U}: Level 2
When this Class becomes level 2, draw two cards.
{4}{U}: Level 3
Whenever you draw a card, put a +1/+1 counter on target creature you control.

Sanctuary Smasher

First strike
Cycling {2}{R} ({2}{R}, Discard this card: Draw a card.)
When you cycle Sanctuary Smasher, put a first strike counter on target creature you control.

Lava Serpent

Haste
Cycling {2} ({2}, Discard this card: Draw a card.)

Wingfold Pteron

Wingfold Pteron enters with your choice of a flying counter or a hexproof counter on it. (A creature with hexproof can't be the target of spells or abilities your opponents control.)

Island

Cinder Storm

Cinder Storm deals 7 damage to any target.

Horizon Scholar

Flying
When Horizon Scholar enters, scry 2. (Look at the top two cards of your library, then put any number of them on the bottom and the rest on top in any order.)

Spellweaver Duo

Assist (Another player can pay up to {6} of this spell's cost.)
When Spellweaver Duo enters, you may return target tapped creature to its owner's hand.

Invading Manticore

When Invading Manticore enters, amass Zombies 2. (Put two +1/+1 counters on an Army you control. It's also a Zombie. If you don't control an Army, create a 0/0 black Zombie Army creature token first.)

Earth-Cult Elemental

Siege Monster — When Earth-Cult Elemental enters, roll a d20.
1—9 | Each player sacrifices a permanent of their choice.
10—19 | Each opponent sacrifices a permanent of their choice.
20 | Each opponent sacrifices two permanents of their choice.

Scour the Laboratory

Delirium — This spell costs {2} less to cast if there are four or more card types among cards in your graveyard.
Draw three cards.

Creative Outburst

Creative Outburst deals 5 damage to any target. Look at the top five cards of your library. Put one of them into your hand and the rest on the bottom of your library in a random order.
{U/R}{U/R}, Discard Creative Outburst: Create a Treasure token.

Book Devourer

Trample
Whenever Book Devourer deals combat damage to a player, you may discard all the cards in your hand. If you do, draw that many cards.

Bond of Passion

Gain control of target creature until end of turn. Untap that creature. It gains haste until end of turn. Bond of Passion deals 2 damage to any other target.

Magmatic Sinkhole

Delve (Each card you exile from your graveyard while casting this spell pays for {1}.)
Magmatic Sinkhole deals 5 damage to target creature or planeswalker.

Accomplished Automaton

Fabricate 1 (When this creature enters, put a +1/+1 counter on it or create a 1/1 colorless Servo artifact creature token.)

Air-Cult Elemental

Flying
Whirlwind — When Air-Cult Elemental enters, return up to one other target creature to its owner's hand.

Read the Tides

Choose one —
• Draw three cards.
• Return up to two target creatures to their owners' hands.

Inferno Jet

Inferno Jet deals 6 damage to target opponent or planeswalker.
Cycling {2} ({2}, Discard this card: Draw a card.)

Meteorite

When Meteorite enters, it deals 2 damage to any target.
{T}: Add one mana of any color.

Prying Eyes

Armillary Sphere

{2}, {T}, Sacrifice Armillary Sphere: Search your library for up to two basic land cards, reveal them, put them into your hand, then shuffle.

Urza's Mine

{T}: Add {C}. If you control an Urza's Power-Plant and an Urza's Tower, add {C}{C} instead.

Boarding Party

Haste
Cascade (When you cast this spell, exile cards from the top of your library until you exile a nonland card that costs less. You may cast it without paying its mana cost. Put the exiled cards on the bottom in a random order.)

Thespian's Stage

{T}: Add {C}.
{2}, {T}: Thespian's Stage becomes a copy of target land, except it has this ability.

Meteor Golem

When Meteor Golem enters, destroy target nonland permanent an opponent controls.

Dusk Legion Dreadnought

Vigilance
Crew 2 (Tap any number of creatures you control with total power 2 or more: This Vehicle becomes an artifact creature until end of turn.)

Mahamoti Djinn

Flying (This creature can't be blocked except by creatures with flying or reach.)

Prophetic Titan

Delirium — When Prophetic Titan enters, choose one. If there are four or more card types among cards in your graveyard, choose both instead.
• Prophetic Titan deals 4 damage to any target.
• Look at the top four cards of your library. Put one of them into your hand and the rest on the bottom of your library in a random order.

Archipelagore

Mutate {5}{U} (If you cast this spell for its mutate cost, put it over or under target non-Human creature you own. They mutate into the creature on top plus all abilities from under it.)
Whenever this creature mutates, tap up to X target creatures, where X is the number of times this creature has mutated. Those creatures don't untap during their controller's next untap step.

Roiling Waters

Return up to two target creatures your opponents control to their owners' hands. Target player draws two cards.

Magma Hellion

Assist (Another player can pay up to {6} of this spell's cost.)
Trample, haste

Worldfire

Exile all permanents. Exile all cards from all hands and graveyards. Each player's life total becomes 1.

Doomskar Titan

When Doomskar Titan enters, creatures you control get +1/+0 and gain haste until end of turn.
Foretell {4}{R} (During your turn, you may pay {2} and exile this card from your hand face down. Cast it on a later turn for its foretell cost.)

Riverwheel Aerialists

Flying
Prowess (Whenever you cast a noncreature spell, this creature gets +1/+1 until end of turn.)

Revolutionist

When Revolutionist enters, return target instant or sorcery card from your graveyard to your hand.
Madness {3}{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.)

Jhoira of the Ghitu

{2}, Exile a nonland card from your hand: Put four time counters on the exiled card. If it doesn't have suspend, it gains suspend. (At the beginning of your upkeep, remove a time counter. When the last is removed, you may cast it without paying its mana cost. If it's a creature, it has haste.)

Frenzied Saddlebrute

Haste
All creatures can attack your opponents and planeswalkers your opponents control as though those creatures had haste.

Snow Day

Tap up to two target creatures. Those creatures don't untap during their controller's next untap step.
Draw two cards, then discard a card.

Opportunity

Seer's Lantern

{T}: Add {C}.
{2}, {T}: Scry 1. (Look at the top card of your library. You may put that card on the bottom.)

Spreading Flames

Spreading Flames deals 6 damage divided as you choose among any number of target creatures.

Gateway Plaza

Gateway Plaza enters tapped.
When Gateway Plaza enters, sacrifice it unless you pay {1}.
{T}: Add one mana of any color.

Ingenuity Engine

Cascade (When you cast this spell, exile cards from the top of your library until you exile a nonland card that costs less. You may cast it without paying its mana cost. Put the exiled cards on the bottom in a random order.)
{1}, {T}, Sacrifice an artifact: Return target artifact you control to its owner's hand.

Run Ashore

Choose one or both —
• The owner of target nonland permanent puts it on their choice of the top or bottom of their library.
• Return target nonland permanent to its owner's hand.

Scrapdiver Serpent

Scrapdiver Serpent can't be blocked as long as defending player controls an artifact.

Thought Monitor

Affinity for artifacts (This spell costs {1} less to cast for each artifact you control.)
Flying
When Thought Monitor enters, draw two cards.

Fiery Fall

Fiery Fall deals 5 damage to target creature.
Basic landcycling {1}{R} ({1}{R}, Discard this card: Search your library for a basic land card, reveal it, put it into your hand, then shuffle.)

Kuldotha Flamefiend

When Kuldotha Flamefiend enters, you may sacrifice an artifact. If you do, Kuldotha Flamefiend deals 4 damage divided as you choose among any number of targets.

Blood Feud

Target creature fights another target creature. (Each deals damage equal to its power to the other.)

Wave-Wing Elemental

Flying
Landfall — Whenever a land you control enters, Wave-Wing Elemental gets +2/+2 until end of turn.

Confiscate

Enchant permanent
You control enchanted permanent.

Prophet of the Peak

When Prophet of the Peak enters, scry 2. (Look at the top two cards of your library, then put any number of them on the bottom and the rest on top in any order.)

Hypothesizzle

Draw two cards. Then you may discard a nonland card. When you do, Hypothesizzle deals 4 damage to target creature.

Slipstream Serpent

Slipstream Serpent can't attack unless defending player controls an Island.
When you control no Islands, sacrifice Slipstream Serpent.
Morph {5}{U} (You may cast this card face down as a 2/2 creature for {3}. Turn it face up any time for its morph cost.)