Seething Song

Argentum Armor

Equipped creature gets +6/+6.
Whenever equipped creature attacks, destroy target permanent.
Equip {6}

Adventuring Gear

Landfall — Whenever a land you control enters, equipped creature gets +2/+2 until end of turn.
Equip {1} ({1}: Attach to target creature you control. Equip only as a sorcery.)

Generator Servant

{T}, Sacrifice Generator Servant: Add {C}{C}. If that mana is spent on a creature spell, it gains haste until end of turn. (That creature can attack and {T} as soon as it comes under your control.)

Active Volcano

Choose one —
• Destroy target blue permanent.
• Return target Island to its owner's hand.

Balduvian Warlord

{T}: Remove target blocking creature from combat. Creatures it was blocking that hadn't become blocked by another creature this combat become unblocked, then it blocks an attacking creature of your choice. Activate only during the declare blockers step.

Vessel of Volatility

{1}{R}, Sacrifice Vessel of Volatility: Add {R}{R}{R}{R}.

Battle Rampart

Defender
{T}: Target creature gains haste until end of turn.

Grinning Ignus

{R}, Return Grinning Ignus to its owner's hand: Add {C}{C}{R}. Activate only as a sorcery.

Mind Stone

{T}: Add {C}.
{1}, {T}, Sacrifice Mind Stone: Draw a card.

Sol Ring

Iron Myr

Magnetic Theft

Attach target Equipment to target creature. (Control of the Equipment doesn't change.)

Crashing Drawbridge

Defender
{T}: Creatures you control gain haste until end of turn.

Balduvian Rage

Target attacking creature gets +X/+0 until end of turn.
Draw a card at the beginning of the next turn's upkeep.

Alchemist's Vial

When Alchemist's Vial enters, draw a card.
{1}, {T}, Sacrifice Alchemist's Vial: Target creature can't attack or block this turn.

Hedron Crawler

{T}: Add {C}. ({C} represents colorless mana.)

Aggression

Enchant non-Wall creature
Enchanted creature has first strike and trample.
At the beginning of the end step of enchanted creature's controller, destroy that creature if it didn't attack this turn.

Aeon Engine

Aeon Engine enters tapped.
{T}, Exile Aeon Engine: Reverse the game's turn order. (For example, if play had proceeded clockwise around the table, it now goes counterclockwise.)

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.

Diamond Lion

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

Ambush

Blocking creatures gain first strike until end of turn.

Arc-Slogger

{R}, Exile the top ten cards of your library: Arc-Slogger deals 2 damage to any target.

Arcane Signet

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

About Face

Switch target creature's power and toughness until end of turn.

Helm of the Host

At the beginning of combat on your turn, create a token that's a copy of equipped creature, except the token isn't legendary. That token gains haste.
Equip {5}

Ricochet Trap

If an opponent cast a blue spell this turn, you may pay {R} rather than pay this spell's mana cost.
Change the target of target spell with a single target.

Mana Seism

Sacrifice any number of lands, then add that much {C}.

Act of Aggression

({R/P} can be paid with either {R} or 2 life.)
Gain control of target creature an opponent controls until end of turn. Untap that creature. It gains haste until end of turn.

Axgard Cavalry

{T}: Target creature gains haste until end of turn. (It can attack and {T} this turn.)

Ballista Wielder

{2}{R}: Ballista Wielder deals 1 damage to any target. A creature dealt damage this way can't block this turn.
Nightbound (If a player casts at least two spells during their own turn, it becomes day next turn.)

Ballista Watcher

{2}{R}, {T}: Ballista Watcher deals 1 damage to any target.
Daybound (If a player casts no spells during their own turn, it becomes night next turn.)

Ballista Watcher // Ballista Wielder

Wily Goblin

When Wily Goblin enters, create a Treasure token. (It's an artifact with "{T}, Sacrifice this artifact: Add one mana of any color.")

Alpha Myr

Magus of the Wheel

{1}{R}, {T}, Sacrifice Magus of the Wheel: Each player discards their hand, then draws seven cards.

Aspect of Manticore

Flash
Enchant creature
When Aspect of Manticore enters, enchanted creature gains first strike until end of turn.
Enchanted creature gets +2/+0.

Dire Fleet Daredevil

First strike
When Dire Fleet Daredevil enters, exile target instant or sorcery card from an opponent's graveyard. You may cast it this turn, and mana of any type can be spent to cast that spell. If that spell would be put into a graveyard, exile it instead.

Pyroclasm

Pyroclasm deals 2 damage to each creature.

By Force

Altar Golem

Trample
Altar Golem's power and toughness are each equal to the number of creatures on the battlefield.
Altar Golem doesn't untap during your untap step.
Tap five untapped creatures you control: Untap Altar Golem.

Burning Anger

Enchant creature
Enchanted creature has "{T}: This creature deals damage equal to its power to any target."

Arc Runner

Haste (This creature can attack and {T} as soon as it comes under your control.)
At the beginning of the end step, sacrifice Arc Runner.

Berserker's Frenzy

Cast this spell only before combat or during combat before blockers are declared.
Roll two d20 and ignore the lower roll.
1—14 | Choose any number of creatures. They block this turn if able.
15—20 | You choose which creatures block this turn and how those creatures block.

Brass Squire

{T}: Attach target Equipment you control to target creature you control.

Skirk Prospector

Ball Lightning

Trample (This creature can deal excess combat damage to the player or planeswalker it's attacking.)
Haste (This creature can attack and {T} as soon as it comes under your control.)
At the beginning of the end step, sacrifice this creature.

Blindblast

Blindblast deals 1 damage to target creature. That creature can't block this turn.
Draw a card.

Mountain

Ornithopter of Paradise

Fire Diamond

Fire Diamond enters tapped.
{T}: Add {R}.

Bravado

Enchant creature
Enchanted creature gets +1/+1 for each other creature you control.

Simian Spirit Guide

Exile Simian Spirit Guide from your hand: Add {R}.

Everflowing Chalice

Multikicker {2} (You may pay an additional {2} any number of times as you cast this spell.)
Everflowing Chalice enters with a charge counter on it for each time it was kicked.
{T}: Add {C} for each charge counter on Everflowing Chalice.

Archetype of Aggression

Creatures you control have trample.
Creatures your opponents control lose trample and can't have or gain trample.

Arcum's Astrolabe

({S} can be paid with one mana from a snow source.)
When Arcum's Astrolabe enters, draw a card.
{1}, {T}: Add one mana of any color.

Abrade

Choose one —
• Abrade deals 3 damage to target creature.
• Destroy target artifact.

Dualcaster Mage

Flash
When Dualcaster Mage enters, copy target instant or sorcery spell. You may choose new targets for the copy.

Battle Hymn

Electric Revelation

As an additional cost to cast this spell, discard a card.
Draw two cards.
Flashback {3}{R} (You may cast this card from your graveyard for its flashback cost and any additional costs. Then exile it.)

Bloodshed Fever

Enchant creature
Enchanted creature attacks each combat if able.

Krark-Clan Stoker

Palladium Myr

Ashling's Prerogative

As Ashling's Prerogative enters, choose odd or even. (Zero is even.)
Each creature with mana value of the chosen quality has haste.
Each creature without mana value of the chosen quality enters tapped.

Twinflame

Strive — This spell costs {2}{R} more to cast for each target beyond the first.
Choose any number of target creatures you control. For each of them, create a token that's a copy of that creature, except it has haste. Exile those tokens at the beginning of the next end step.

Mine Collapse

If it's your turn, you may sacrifice a Mountain rather than pay this spell's mana cost.
Mine Collapse deals 5 damage to target creature or planeswalker.

An-Zerrin Ruins

As An-Zerrin Ruins enters, choose a creature type.
Creatures of the chosen type don't untap during their controllers' untap steps.

Akoum Hellhound

Landfall — Whenever a land you control enters, Akoum Hellhound gets +2/+2 until end of turn.

Godo, Bandit Warlord

When Godo, Bandit Warlord enters, you may search your library for an Equipment card, put it onto the battlefield, then shuffle.
Whenever Godo attacks for the first time each turn, untap it and all Samurai you control. After this phase, there is an additional combat phase.

Manakin

Delina, Wild Mage

Whenever Delina, Wild Mage attacks, choose target creature you control, then roll a d20.
1—14 | Create a tapped and attacking token that's a copy of that creature, except it's not legendary and it has "At end of combat, exile this creature."
15—20 | Create one of those tokens. You may roll again.