The Jolly Balloon Man

Haste
{1}, {T}: Create a token that's a copy of another target creature you control, except it's a 1/1 red Balloon creature in addition to its other colors and types and it has flying and haste. Sacrifice it at the beginning of the next end step. Activate only as a sorcery.

Mascot Interception

This spell costs {3} less to cast if it targets a creature token.
Gain control of target creature until end of turn. Untap that creature. It gets +2/+0 and gains haste until end of turn.

Goblin Cratermaker

{1}, Sacrifice this creature: Choose one —
• This creature deals 2 damage to target creature.
• Destroy target colorless nonland permanent.

Mages' Contest

You and target spell's controller bid life. You start the bidding with a bid of 1. In turn order, each player may top the high bid. The bidding ends if the high bid stands. The high bidder loses life equal to the high bid. If you win the bidding, counter that spell.

Ancient Copper Dragon

Flying
Whenever this creature deals combat damage to a player, roll a d20. You create a number of Treasure tokens equal to the result.

Winds of Abandon

Exile target creature you don't control. For each creature exiled this way, its controller searches their library for a basic land card. Those players put those cards onto the battlefield tapped, then shuffle.
Overload {4}{W}{W} (You may cast this spell for its overload cost. If you do, change "target" in its text to "each.")

Dauntless Aven

Flying
Whenever this creature attacks, untap target creature you control.

Vengeful Possession

Gain control of target creature until end of turn. Untap it. It gains haste until end of turn. You may discard a card. If you do, draw a card.

Seize the Spotlight

Each opponent chooses fame or fortune. For each player who chose fame, gain control of a creature that player controls until end of turn. Untap those creatures and they gain haste until end of turn. For each player who chose fortune, you draw a card and create a Treasure token.

Mark of Mutiny

Gain control of target creature until end of turn. Put a +1/+1 counter on it and untap it. That creature gains haste until end of turn. (It can attack and {T} this turn.)

Mass Mutiny

For each opponent, gain control of up to one target creature that player controls until end of turn. Untap those creatures. They gain haste until end of turn.

Patriar's Seal

{T}: Add one mana of any color.
{1}, {T}: Untap target legendary creature you control.

Arcane Signet

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

Mob Rule

Choose one —
• Gain control of all creatures with power 4 or greater until end of turn. Untap those creatures. They gain haste until end of turn.
• Gain control of all creatures with power 3 or less until end of turn. Untap those creatures. They gain haste until end of turn.

Word of Seizing

Split second (As long as this spell is on the stack, players can't cast spells or activate abilities that aren't mana abilities.)
Untap target permanent and gain control of it until end of turn. It gains haste until end of turn.

Angelic Purge

As an additional cost to cast this spell, sacrifice a permanent.
Exile target artifact, creature, or enchantment.

Deflecting Swat

If you control a commander, you may cast this spell without paying its mana cost.
You may choose new targets for target spell or ability.

Tormenting Voice

As an additional cost to cast this spell, discard a card.
Draw two cards.

Swords to Plowshares

Exile target creature. Its controller gains life equal to its power.

Thistledown Players

Whenever this creature attacks, untap target nonland permanent.

Boros Signet

Fiendish Duo

First strike (This creature deals combat damage before creatures without first strike.)
If a source would deal damage to an opponent, it deals double that damage to that player instead.

Furnace Celebration

Whenever you sacrifice another permanent, you may pay {2}. If you do, this enchantment deals 2 damage to any target.

Canoptek Wraith

Wraith Form — This creature can't be blocked.
Transdimensional Scout — When this creature deals combat damage to a player, you may pay {3} and sacrifice it. If you do, choose a land you control. Then search your library for up to two basic land cards which have the same name as the chosen land, put them onto the battlefield tapped, then shuffle.

Thousand-Year Elixir

You may activate abilities of creatures you control as though those creatures had haste.
{1}, {T}: Untap target creature.

Bolt Bend

This spell costs {3} less to cast if you control a creature with power 4 or greater.
Change the target of target spell or ability with a single target.

Angrath's Marauders

If a source you control would deal damage to a permanent or player, it deals double that damage to that permanent or player instead.

Call for Aid

Gain control of all creatures target opponent controls until end of turn. Untap those creatures. They gain haste until end of turn. You can't attack that player this turn. You can't sacrifice those creatures this turn.

Wrath of God

Destroy all creatures. They can't be regenerated.

Eldrazi Monument

Creatures you control get +1/+1 and have flying and indestructible.
At the beginning of your upkeep, sacrifice a creature. If you can't, sacrifice this artifact.

Sol Ring

Emberwilde Augur

Sacrifice this creature: It deals 3 damage to target player or planeswalker. Activate only during your upkeep.

Fear of Missing Out

When this creature enters, discard a card, then draw a card.
Delirium — Whenever this creature attacks for the first time each turn, if there are four or more card types among cards in your graveyard, untap target creature. After this phase, there is an additional combat phase.

Path to Exile

Exile target creature. Its controller may search their library for a basic land card, put that card onto the battlefield tapped, then shuffle.

Ancient Gold Dragon

Flying
Whenever this creature deals combat damage to a player, roll a d20. You create a number of 1/1 blue Faerie Dragon creature tokens with flying equal to the result.

Untimely Malfunction

Choose one —
• Destroy target artifact.
• Change the target of target spell or ability with a single target.
• One or two target creatures can't block this turn.

Fireflux Squad

Haste
Whenever this creature attacks, you may exile another target attacking creature you control. If you do, reveal cards from the top of your library until you reveal a creature card. Put that card onto the battlefield tapped and attacking and the rest on the bottom of your library in a random order.

Dragon Mage

Flying
Whenever this creature deals combat damage to a player, each player discards their hand, then draws seven cards.

Parting Gust

Gift a tapped Fish (You may promise an opponent a gift as you cast this spell. If you do, they create a tapped 1/1 blue Fish creature token before its other effects.)
Exile target nontoken creature. If the gift wasn't promised, return that card to the battlefield under its owner's control with a +1/+1 counter on it at the beginning of the next end step.

Big Score

As an additional cost to cast this spell, discard a card.
Draw two cards and create two Treasure tokens. (They're artifacts with "{T}, Sacrifice this token: Add one mana of any color.")

Dreamshaper Shaman

At the beginning of your end step, you may pay {2}{R} and sacrifice a nonland permanent. If you do, reveal cards from the top of your library until you reveal a nonland permanent card. Put that card onto the battlefield and the rest on the bottom of your library in a random order.

Deflecting Palm

The next time a source of your choice would deal damage to you this turn, prevent that damage. If damage is prevented this way, Deflecting Palm deals that much damage to that source's controller.

Aspiring Champion

Menace
Ruinous Ascension — When this creature deals combat damage to a player, sacrifice it. If you do, reveal cards from the top of your library until you reveal a creature card. Put that card onto the battlefield, then shuffle the rest into your library. If that creature is a Demon, it deals damage equal to its power to each opponent.

Havoc Jester

Whenever you sacrifice a permanent, this creature deals 1 damage to any target.

Barbed Shocker

Trample, haste
Whenever this creature deals damage to a player, that player discards all the cards in their hand, then draws that many cards.

Bloodthirster

Flying, trample
Whenever this creature deals combat damage to a player, untap it. After this phase, there is an additional combat phase.
This creature can't attack a player it has already attacked this turn.

Tibalt's Trickery

Counter target spell. Choose 1, 2, or 3 at random. Its controller mills that many cards, then exiles cards from the top of their library until they exile a nonland card with a different name than that spell. They may cast that card without paying its mana cost. Then they put the exiled cards on the bottom of their library in a random order.

Militia Rallier

This creature can't attack alone.
Whenever this creature attacks, untap target creature.

Exuberant Firestoker

At the beginning of your end step, if you control a creature with power 5 or greater, you may have this creature deal 2 damage to target player or planeswalker.
{T}: Add {C}.

Brimstone Trebuchet

Defender, reach
{T}: This creature deals 1 damage to each opponent.
Whenever a Knight you control enters, untap this creature.

Balor

Flying
Whenever this creature attacks or dies, choose one or more. Each mode must target a different player.
• Target opponent draws three cards, then discards three cards at random.
• Target opponent sacrifices a nontoken artifact of their choice.
• This creature deals damage to target opponent equal to the number of cards in their hand.

Blood Aspirant

Whenever you sacrifice a permanent, put a +1/+1 counter on this creature.
{1}{R}, {T}, Sacrifice a creature or enchantment: This creature deals 1 damage to target creature. That creature can't block this turn.

Zealous Conscripts

Haste
When this creature enters, gain control of target permanent until end of turn. Untap that permanent. It gains haste until end of turn.

Emberwilde Captain

When this creature enters, you become the monarch.
Whenever an opponent attacks you while you're the monarch, this creature deals damage to that player equal to the number of cards in their hand.