Reconnaissance

{0}: Remove target attacking creature you control from combat and untap it. (If you activate during end of combat, the creature will untap after it deals combat damage.)

Marauding Maulhorn

Marauding Maulhorn attacks each combat if able unless you control a creature named Advocate of the Beast.

Flameborn Hellion

Haste
Flameborn Hellion attacks each combat if able.

Reckless Brute

Haste (This creature can attack and {T} as soon as it comes under your control.)
Reckless Brute attacks each combat if able.

Oathsworn Knight

Oathsworn Knight enters with four +1/+1 counters on it.
Oathsworn Knight attacks each combat if able.
If damage would be dealt to Oathsworn Knight while it has a +1/+1 counter on it, prevent that damage and remove a +1/+1 counter from it.

Crazed Goblin

Crazed Goblin attacks each combat if able.

Evolving Wilds

{T}, Sacrifice Evolving Wilds: Search your library for a basic land card, put it onto the battlefield tapped, then shuffle.

Swamp

Khârn the Betrayer

Berzerker — Khârn the Betrayer attacks or blocks each combat if able.
Sigil of Corruption — When you lose control of Khârn the Betrayer, draw two cards.
The Betrayer — If damage would be dealt to Khârn the Betrayer, prevent that damage and an opponent of your choice gains control of it.

Akoum Firebird

Flying, haste
Akoum Firebird attacks each combat if able.
Landfall — Whenever a land you control enters, you may pay {4}{R}{R}. If you do, return Akoum Firebird from your graveyard to the battlefield.

Boros Garrison

Boros Garrison enters tapped.
When Boros Garrison enters, return a land you control to its owner's hand.
{T}: Add {R}{W}.

Valley Dasher

Haste
Valley Dasher attacks each combat if able.

Knight Rampager

Trample
Frenzied Rampage — At the beginning of combat on your turn, choose an opponent at random. Knight Rampager attacks that player this combat if able.
When Knight Rampager dies, it deals 4 damage to target opponent chosen at random.

Red Herring

Haste
Red Herring attacks each combat if able.
{2}, Sacrifice Red Herring: Draw a card.

Mountain

Xantcha, Sleeper Agent

Xantcha, Sleeper Agent enters under the control of an opponent of your choice.
Xantcha attacks each combat if able and can't attack its owner or planeswalkers its owner controls.
{3}: Xantcha's controller loses 2 life and you draw a card. Any player may activate this ability.

Haktos the Unscarred

Haktos the Unscarred attacks each combat if able.
As Haktos enters, choose 2, 3, or 4 at random.
Haktos has protection from each mana value other than the chosen number.

Goblin Brigand

Goblin Brigand attacks each combat if able.

Flamewake Phoenix

Flying, haste
Flamewake Phoenix attacks each combat if able.
Ferocious — At the beginning of combat on your turn, if you control a creature with power 4 or greater, you may pay {R}. If you do, return Flamewake Phoenix from your graveyard to the battlefield.

Arcum's Whistle

{3}, {T}: Choose target non-Wall creature the active player has controlled continuously since the beginning of the turn. That player may pay {X}, where X is that mana value. If they don't pay, the creature attacks this turn if able, and at the beginning of the next end step, destroy it if it didn't attack this turn. Activate only before attackers are declared.

Alpine Guide

When Alpine Guide enters, you may search your library for a Mountain card, put that card onto the battlefield tapped, then shuffle.
Alpine Guide attacks each combat if able.
When Alpine Guide leaves the battlefield, sacrifice a Mountain.

Berserkers of Blood Ridge

Berserkers of Blood Ridge attacks each combat if able.

For the Emperor!

Creatures you control get +2/+2 and gain vigilance and lifelink until end of turn.

Utvara Scalper

Flying
Utvara Scalper attacks each combat if able.

Frontline Rebel

Frontline Rebel attacks each combat if able.

Kuldotha Ringleader

Battle cry (Whenever this creature attacks, each other attacking creature gets +1/+0 until end of turn.)
Kuldotha Ringleader attacks each combat if able.

Terramorphic Expanse

{T}, Sacrifice Terramorphic Expanse: Search your library for a basic land card, put it onto the battlefield tapped, then shuffle.

Warmonger Hellkite

Flying
All creatures attack each combat if able.
{1}{R}: Attacking creatures get +1/+0 until end of turn.

Rakdos Carnarium

Rakdos Carnarium enters tapped.
When Rakdos Carnarium enters, return a land you control to its owner's hand.
{T}: Add {B}{R}.

Daring Fiendbonder

Haste
Daring Fiendbonder attacks each combat if able.
{1}{B}, Exile Daring Fiendbonder from your graveyard: Put an indestructible counter on target creature. Activate only as a sorcery.

Tectonic Fiend

Echo {4}{R}{R} (At the beginning of your upkeep, if this came under your control since the beginning of your last upkeep, sacrifice it unless you pay its echo cost.)
Tectonic Fiend attacks each combat if able.

Nomad Outpost

Nomad Outpost enters tapped.
{T}: Add {R}, {W}, or {B}.

Graaz, Unstoppable Juggernaut

Juggernauts you control attack each combat if able.
Juggernauts you control can't be blocked by Walls.
Other creatures you control have base power and toughness 5/3 and are Juggernauts in addition to their other creature types.

Kill-Suit Cultist

Kill-Suit Cultist attacks each combat if able.
{B}, Sacrifice Kill-Suit Cultist: The next time damage would be dealt to target creature this turn, destroy that creature instead.

Dihada, Binder of Wills

+2: Up to one target legendary creature gains vigilance, lifelink, and indestructible until your next turn.
−3: Reveal the top four cards of your library. Put any number of legendary cards from among them into your hand and the rest into your graveyard. Create a Treasure token for each card put into your graveyard this way.
−11: Gain control of all nonland permanents until end of turn. Untap them. They gain haste until end of turn.
Dihada, Binder of Wills can be your commander.

Bloodcrazed Neonate

Bloodcrazed Neonate attacks each combat if able.
Whenever Bloodcrazed Neonate deals combat damage to a player, put a +1/+1 counter on it.

Angel's Trumpet

All creatures have vigilance.
At the beginning of each player's end step, tap all untapped creatures that player controls that didn't attack this turn. Angel's Trumpet deals damage to the player equal to the number of creatures tapped this way.

Embercleave

Flash
This spell costs {1} less to cast for each attacking creature you control.
When Embercleave enters, attach it to target creature you control.
Equipped creature gets +1/+1 and has double strike and trample.
Equip {3}

Manticore Eternal

Afflict 3 (Whenever this creature becomes blocked, defending player loses 3 life.)
Manticore Eternal attacks each combat if able.

Orzhov Signet

Cathars' Crusade

Whenever a creature you control enters, put a +1/+1 counter on each creature you control.

Impetuous Sunchaser

Flying, haste
Impetuous Sunchaser attacks each combat if able.

Sol Ring

Unbreakable Formation

Creatures you control gain indestructible until end of turn.
Addendum — If you cast this spell during your main phase, put a +1/+1 counter on each of those creatures and they gain vigilance until end of turn.

Sparring Regimen

When Sparring Regimen enters, learn. (You may reveal a Lesson card you own from outside the game and put it into your hand, or discard a card to draw a card.)
Whenever you attack, put a +1/+1 counter on target attacking creature and untap it.

Plains

Juggernaut

Juggernaut attacks each combat if able.
Juggernaut can't be blocked by Walls.

Reckless Cohort

Reckless Cohort attacks each combat if able unless you control another Ally.

Sabertooth Alley Cat

Sabertooth Alley Cat attacks each combat if able.
{1}{R}: Creatures without defender can't block Sabertooth Alley Cat this turn.

Lightning Greaves

Equipped creature has haste and shroud. (It can't be the target of spells or abilities.)
Equip {0}

Ulamog's Crusher

Annihilator 2 (Whenever this creature attacks, defending player sacrifices two permanents of their choice.)
Ulamog's Crusher attacks each combat if able.

Gleam of Battle

Whenever a creature you control attacks, put a +1/+1 counter on it.

Stroke of Midnight

Destroy target nonland permanent. Its controller creates a 1/1 white Human creature token.

Swiftfoot Boots

Equipped creature has hexproof and haste. (It can't be the target of spells or abilities your opponents control.)
Equip {1}

Dauthi Slayer

Shadow (This creature can block or be blocked by only creatures with shadow.)
Dauthi Slayer attacks each combat if able.

Battle-Mad Ronin

Bushido 2 (Whenever this creature blocks or becomes blocked, it gets +2/+2 until end of turn.)
Battle-Mad Ronin attacks each combat if able.

Settle the Wreckage

Exile all attacking creatures target player controls. That player may search their library for that many basic land cards, put those cards onto the battlefield tapped, then shuffle.

Mishra's Juggernaut

Trample
Mishra's Juggernaut attacks each combat if able.
Unearth {5}{R} ({5}{R}: Return this card from your graveyard to the battlefield. It gains haste. Exile it at the beginning of the next end step or if it would leave the battlefield. Unearth only as a sorcery.)

Boros Signet

Phyrexian Juggernaut

Infect (This creature deals damage to creatures in the form of -1/-1 counters and to players in the form of poison counters.)
Phyrexian Juggernaut attacks each combat if able.

Insatiable Gorgers

Insatiable Gorgers attacks each combat if able.
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.)

Orzhov Basilica

Orzhov Basilica enters tapped.
When Orzhov Basilica enters, return a land you control to its owner's hand.
{T}: Add {W}{B}.

Castle Embereth

Castle Embereth enters tapped unless you control a Mountain.
{T}: Add {R}.
{1}{R}{R}, {T}: Creatures you control get +1/+0 until end of turn.

Mogis's Warhound

Bestow {2}{R} (If you cast this card for its bestow cost, it's an Aura spell with enchant creature. It becomes a creature again if it's not attached to a creature.)
Mogis's Warhound attacks each combat if able.
Enchanted creature gets +2/+2 and attacks each combat if able.

Zurgo Helmsmasher

Haste
Zurgo Helmsmasher attacks each combat if able.
During your turn, Zurgo Helmsmasher has indestructible.
Whenever a creature dealt damage by Zurgo Helmsmasher this turn dies, put a +1/+1 counter on Zurgo Helmsmasher.

Deathbellow Raider

Deathbellow Raider attacks each combat if able.
{2}{B}: Regenerate Deathbellow Raider.

Bloodrock Cyclops

Bloodrock Cyclops attacks each combat if able.

Vault of the Archangel

{T}: Add {C}.
{2}{W}{B}, {T}: Creatures you control gain deathtouch and lifelink until end of turn.

Monstrous Carabid

Monstrous Carabid attacks each combat if able.
Cycling {B/R} ({B/R}, Discard this card: Draw a card.)

Arcane Signet

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

Underworld Rage-Hound

Underworld Rage-Hound attacks each combat if able.
Escape—{3}{R}, Exile three other cards from your graveyard. (You may cast this card from your graveyard for its escape cost.)
Underworld Rage-Hound escapes with a +1/+1 counter on it.

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.)

True Conviction

Creatures you control have double strike and lifelink.

Thran War Machine

Echo {4} (At the beginning of your upkeep, if this came under your control since the beginning of your last upkeep, sacrifice it unless you pay its echo cost.)
Thran War Machine attacks each combat if able.