Goblin Archaeologist

{R}, {T}: Flip a coin. If you win the flip, destroy target artifact and untap this creature. If you lose the flip, sacrifice this creature.

Shivan Reef

{T}: Add {C}.
{T}: Add {U} or {R}. This land deals 1 damage to you.

Fling

As an additional cost to cast this spell, sacrifice a creature.
Fling deals damage equal to the sacrificed creature's power to any target.

The Gold Saucer

{T}: Add {C}.
{2}, {T}: Flip a coin. If you win the flip, create a Treasure token.
{3}, {T}, Sacrifice two artifacts: Draw a card.

Academy Ruins

{T}: Add {C}.
{1}{U}, {T}: Put target artifact card from your graveyard on top of your library.

Chaos Warp

The owner of target permanent shuffles it into their library, then reveals the top card of their library. If it's a permanent card, they put it onto the battlefield.

Planar Chaos

At the beginning of your upkeep, flip a coin. If you lose the flip, sacrifice this enchantment.
Whenever a player casts a spell, that player flips a coin. If they lose the flip, counter that spell.

Desperate Gambit

Choose a source you control and flip a coin. If you win the flip, the next time that source would deal damage this turn, it deals double that damage instead. If you lose the flip, the next time it would deal damage this turn, prevent that damage.

Training Center

This land enters tapped unless you have two or more opponents.
{T}: Add {U} or {R}.

Command Tower

{T}: Add one mana of any color in your commander's color identity.

Zndrsplt, Eye of Wisdom

Partner with Okaun, Eye of Chaos (When this creature enters, target player may put Okaun into their hand from their library, then shuffle.)
At the beginning of combat on your turn, flip a coin until you lose a flip.
Whenever a player wins a coin flip, draw a card.

Crooked Scales

{4}, {T}: Flip a coin. If you win the flip, destroy target creature an opponent controls. If you lose the flip, destroy target creature you control unless you pay {3} and repeat this process.

Crazed Firecat

When this creature enters, flip a coin until you lose a flip. Put a +1/+1 counter on this creature for each flip you won.

Goblin Electromancer

Instant and sorcery spells you cast cost {1} less to cast.

Thud

As an additional cost to cast this spell, sacrifice a creature.
Thud deals damage equal to the sacrificed creature's power to any target.

Blasphemous Act

This spell costs {1} less to cast for each creature on the battlefield.
Blasphemous Act deals 13 damage to each creature.

Talisman of Creativity

{T}: Add {C}.
{T}: Add {U} or {R}. This artifact deals 1 damage to you.

Goblin Assassin

Whenever this creature or another Goblin enters, each player flips a coin. Each player whose coin comes up tails sacrifices a creature of their choice.

Mutalith Vortex Beast

Trample
Warp Vortex — When this creature enters, flip a coin for each opponent you have. For each flip you win, draw a card. For each flip you lose, this creature deals 3 damage to that player.

Tavern Scoundrel

Whenever you win a coin flip, create two Treasure tokens. (They're artifacts with "{T}, Sacrifice this token: Add one mana of any color.")
{1}, {T}, Sacrifice another permanent: Flip a coin.

Whispersilk Cloak

Equipped creature can't be blocked and has shroud. (It can't be the target of spells or abilities.)
Equip {2}

Impulsive Maneuvers

Whenever a creature attacks, flip a coin. If you win the flip, the next time that creature would deal combat damage this turn, it deals double that damage instead. If you lose the flip, the next time that creature would deal combat damage this turn, prevent that damage.

Fiery Gambit

Flip a coin until you lose a flip or choose to stop flipping. If you lose a flip, Fiery Gambit has no effect. If you win one or more flips, Fiery Gambit deals 3 damage to target creature. If you win two or more flips, Fiery Gambit deals 6 damage to each opponent. If you win three or more flips, draw nine cards and untap all lands you control.

Gamble

Search your library for a card, put that card into your hand, discard a card at random, then shuffle.

Fabricate

Search your library for an artifact card, reveal it, put it into your hand, then shuffle.

Vandalblast

Destroy target artifact you don't control.
Overload {4}{R} (You may cast this spell for its overload cost. If you do, change "target" in its text to "each.")

Game of Chaos

Flip a coin. If you win the flip, you gain 1 life and target opponent loses 1 life, and you decide whether to flip again. If you lose the flip, you lose 1 life and that opponent gains 1 life, and that player decides whether to flip again. Double the life stakes with each flip.

Breeches, the Blastmaker

Menace
Whenever you cast your second spell each turn, you may sacrifice an artifact. If you do, flip a coin. When you win the flip, copy that spell. You may choose new targets for the copy. When you lose the flip, Breeches deals damage equal to that spell's mana value to any target.

Sulfur Falls

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

Sorcerer's Strongbox

{2}, {T}: Flip a coin. If you win the flip, sacrifice this artifact and draw three cards.

Karplusan Minotaur

Cumulative upkeep—Flip a coin. (At the beginning of your upkeep, put an age counter on this permanent, then sacrifice it unless you pay its upkeep cost for each age counter on it.)
Whenever you win a coin flip, this creature deals 1 damage to any target.
Whenever you lose a coin flip, this creature deals 1 damage to any target of an opponent's choice.

Boompile

{T}: Flip a coin. If you win the flip, destroy all nonland permanents.

Fiery Islet

{T}, Pay 1 life: Add {U} or {R}.
{1}, {T}, Sacrifice this land: Draw a card.

Winter Sky

Flip a coin. If you win the flip, Winter Sky deals 1 damage to each creature and each player. If you lose the flip, each player draws a card.

Frostboil Snarl

As this land enters, you may reveal an Island or Mountain card from your hand. If you don't, this land enters tapped.
{T}: Add {U} or {R}.

Goblin Bomb

At the beginning of your upkeep, you may flip a coin. If you win the flip, put a fuse counter on this enchantment. If you lose the flip, remove a fuse counter from this enchantment.
Remove five fuse counters from this enchantment and sacrifice it: It deals 20 damage to target player or planeswalker.

Triskaidekaphile

You have no maximum hand size.
At the beginning of your upkeep, if you have exactly thirteen cards in your hand, you win the game.
{3}{U}: Draw a card.

Reliquary Tower

You have no maximum hand size.
{T}: Add {C}.

Path of Ancestry

This land enters tapped.
{T}: Add one mana of any color in your commander's color identity. When that mana is spent to cast a creature spell that shares a creature type with your commander, scry 1. (Look at the top card of your library. You may put that card on the bottom.)

Faithless Looting

Draw two cards, then discard two cards.
Flashback {2}{R} (You may cast this card from your graveyard for its flashback cost. Then exile it.)

Tide of War

Whenever one or more creatures block, flip a coin. If you win the flip, each blocking creature is sacrificed by its controller. If you lose the flip, each blocked creature is sacrificed by its controller.

Ferrous Lake

Yusri, Fortune's Flame

Flying
Whenever Yusri attacks, choose a number between 1 and 5. Flip that many coins. For each flip you win, draw a card. For each flip you lose, Yusri deals 2 damage to you. If you won five flips this way, you may cast spells from your hand this turn without paying their mana costs.

Temple of Epiphany

This land enters tapped.
When this land enters, scry 1. (Look at the top card of your library. You may put that card on the bottom.)
{T}: Add {U} or {R}.

Edgar, King of Figaro

When Edgar enters, draw a card for each artifact you control.
Two-Headed Coin — The first time you flip one or more coins each turn, those coins come up heads and you win those flips.

Goblin Festival

{2}: This enchantment deals 1 damage to any target. Flip a coin. If you lose the flip, choose one of your opponents. That player gains control of this enchantment.

Frenetic Efreet

Flying
{0}: Flip a coin. If you win the flip, this creature phases out. If you lose the flip, sacrifice this creature. (While it's phased out, it's treated as though it doesn't exist. It phases in before you untap during your next untap step.)

Goblin Bangchuckers

{T}: Flip a coin. If you win the flip, this creature deals 2 damage to any target. If you lose the flip, this creature deals 2 damage to itself.

Mirror March

Whenever a nontoken creature you control enters, flip a coin until you lose a flip. For each flip you won, create a token that's a copy of that creature. Those tokens gain haste. Exile them at the beginning of the next end step.

Izzet Signet

Island

Chance Encounter

Whenever you win a coin flip, put a luck counter on this enchantment.
At the beginning of your upkeep, if this enchantment has ten or more luck counters on it, you win the game.

Mind Stone

{T}: Add {C}.
{1}, {T}, Sacrifice this artifact: Draw a card.

Okaun, Eye of Chaos

Partner with Zndrsplt, Eye of Wisdom (When this creature enters, target player may put Zndrsplt into their hand from their library, then shuffle.)
At the beginning of combat on your turn, flip a coin until you lose a flip.
Whenever a player wins a coin flip, double Okaun's power and toughness until end of turn.

Cascade Bluffs

{T}: Add {C}.
{U/R}, {T}: Add {U}{U}, {U}{R}, or {R}{R}.

Pongify

Destroy target creature. It can't be regenerated. Its controller creates a 3/3 green Ape creature token.

Chaotic Strike

Cast this spell only during combat after blockers are declared.
Flip a coin. If you win the flip, target creature gets +1/+1 until end of turn.
Draw a card.

Chandra's Ignition

Target creature you control deals damage equal to its power to each other creature and each opponent.

Invert Polarity

Choose target spell, then flip a coin. If you win the flip, gain control of that spell and you may choose new targets for it. If you lose the flip, counter that spell.

Mountain

Izzet Boilerworks

This land enters tapped.
When this land enters, return a land you control to its owner's hand.
{T}: Add {U}{R}.

Rogue's Passage

{T}: Add {C}.
{4}, {T}: Target creature can't be blocked this turn.

Skyclaw Thrash

Whenever this creature attacks, flip a coin. If you win the flip, this creature gets +1/+1 and gains flying until end of turn.

Plasma Caster

Equipped creature gets +1/+1.
Whenever equipped creature attacks, you get {E}{E} (two energy counters).
Pay {E}{E}: Choose target creature that's blocking equipped creature. Flip a coin. If you win the flip, exile the chosen creature. Otherwise, this Equipment deals 1 damage to it.
Equip {2}

Volatile Rig

Trample
This creature attacks each combat if able.
Whenever this creature is dealt damage, flip a coin. If you lose the flip, sacrifice this creature.
When this creature dies, flip a coin. If you lose the flip, it deals 4 damage to each creature and each player.

Bottle of Suleiman

{1}, Sacrifice this artifact: Flip a coin. If you win the flip, create a 5/5 colorless Djinn artifact creature token with flying. If you lose the flip, this artifact deals 5 damage to you.

Thought Vessel

Squee's Revenge

Choose a number. Flip a coin that many times or until you lose a flip, whichever comes first. If you win all the flips, draw two cards for each flip.

Creepy Doll

Indestructible
Whenever this creature deals combat damage to a creature, flip a coin. If you win the flip, destroy that creature.

Goblin Traprunner

Whenever this creature attacks, flip three coins. For each flip you win, create a 1/1 red Goblin creature token that's tapped and attacking.

Temur Battle Rage

Target creature gains double strike until end of turn.
Ferocious — That creature also gains trample until end of turn if you control a creature with power 4 or greater.

Krark's Thumb

If you would flip a coin, instead flip two coins and ignore one.

Mogg Assassin

{T}: You choose target creature an opponent controls, and that opponent chooses target creature. Flip a coin. If you win the flip, destroy the creature you chose. If you lose the flip, destroy the creature your opponent chose.

Stormcarved Coast

This land enters tapped unless you control two or more other lands.
{T}: Add {U} or {R}.

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.

Slip Through Space

Devoid (This card has no color.)
Target creature can't be blocked this turn.
Draw a card.

Steam Vents

({T}: Add {U} or {R}.)
As this land enters, you may pay 2 life. If you don't, it enters tapped.

Mana Clash

You and target opponent each flip a coin. Mana Clash deals 1 damage to each player whose coin comes up tails. Repeat this process until both players' coins come up heads on the same flip.

Arcane Signet

Goblin Kaboomist

At the beginning of your upkeep, create a colorless artifact token named Land Mine with "{R}, Sacrifice this token: This token deals 2 damage to target attacking creature without flying." Then flip a coin. If you lose the flip, this creature deals 2 damage to itself.

Sol Ring

Soul's Fire

Target creature you control deals damage equal to its power to any target.

Krark, the Thumbless

Whenever you cast an instant or sorcery spell, flip a coin. If you lose the flip, return that spell to its owner's hand. If you win the flip, copy that spell, and you may choose new targets for the copy.
Partner (You can have two commanders if both have partner.)