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}

Hardened Berserker

Whenever Hardened Berserker attacks, the next spell you cast this turn costs {1} less to cast.

Flamerush Rider

Whenever Flamerush Rider attacks, create a token that's a copy of another target attacking creature and that's tapped and attacking. Exile the token at end of combat.
Dash {2}{R}{R} (You may cast this spell for its dash cost. If you do, it gains haste, and it's returned from the battlefield to its owner's hand at the beginning of the next end step.)

Sol Ring

Cyclops Gladiator

Whenever Cyclops Gladiator attacks, you may have it deal damage equal to its power to target creature defending player controls. If you do, that creature deals damage equal to its power to Cyclops Gladiator.

Goblin War Drums

Creatures you control have menace. (They can't be blocked except by two or more creatures.)

Markov Blademaster

Double strike
Whenever Markov Blademaster deals combat damage to a player, put a +1/+1 counter on it.

Boldwyr Intimidator

Cowards can't block Warriors.
{R}: Target creature becomes a Coward until end of turn.
{2}{R}: Target creature becomes a Warrior until end of turn.

Mind Stone

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

Paragon of Fierce Defiance

Other red creatures you control get +1/+1.
{R}, {T}: Another target red creature you control gains haste until end of turn. (It can attack and {T} this turn.)

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.

Stormblood Berserker

Bloodthirst 2 (If an opponent was dealt damage this turn, this creature enters with two +1/+1 counters on it.)
Menace (This creature can't be blocked except by two or more creatures.)

Crash Through

Creatures you control gain trample until end of turn. (A creature with trample can deal excess combat damage to the player or planeswalker it's attacking.)
Draw a card.

Cathartic Reunion

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

Kazuul, Tyrant of the Cliffs

Whenever a creature an opponent controls attacks, if you're the defending player, create a 3/3 red Ogre creature token unless that creature's controller pays {3}.

Brighthearth Banneret

Elemental spells and Warrior spells you cast cost {1} less to cast.
Reinforce 1—{1}{R} ({1}{R}, Discard this card: Put a +1/+1 counter on target creature.)

Devilish Valet

Trample, haste
Alliance — Whenever another creature you control enters, double Devilish Valet's power until end of turn.

Ash Zealot

First strike, haste
Whenever a player casts a spell from a graveyard, Ash Zealot deals 3 damage to that player.

Caged Sun

As Caged Sun enters, choose a color.
Creatures you control of the chosen color get +1/+1.
Whenever a land's ability causes you to add one or more mana of the chosen color, add one additional mana of that color.

Goma Fada Vanguard

Whenever Goma Fada Vanguard attacks, target creature an opponent controls with power less than or equal to the number of Warriors you control can't block this turn.

Arni Brokenbrow

Haste
Boast — {1}: You may change Arni Brokenbrow's base power to 1 plus the greatest power among other creatures you control until end of turn. (Activate only if this creature attacked this turn and only once each turn.)

Chaos Terminator Lord

Lord of Chaos — At the beginning of combat on your turn, another target creature you control gains double strike until end of turn.

Warchief Giant

Haste
Myriad (Whenever this creature attacks, for each opponent other than defending player, you may create a token copy that's tapped and attacking that player or a planeswalker they control. Exile the tokens at end of combat.)

Wild Guess

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

Koth, Fire of Resistance

+2: Search your library for a basic Mountain card, reveal it, put it into your hand, then shuffle.
−3: Koth, Fire of Resistance deals damage to target creature equal to the number of Mountains you control.
−7: You get an emblem with "Whenever a Mountain you control enters, this emblem deals 4 damage to any target."

Borderland Marauder

Whenever Borderland Marauder attacks, it gets +2/+0 until end of turn.

Sardian Cliffstomper

As long as it's your turn and you control four or more Mountains, Sardian Cliffstomper gets +X/+0, where X is the number of Mountains you control.

Tormenting Voice

Arni Metalbrow

Whenever a creature you control attacks or a creature you control enters attacking, you may pay {1}{R}. If you do, you may put a creature card with mana value less than that creature's mana value from your hand onto the battlefield tapped and attacking.

Rograkh, Son of Rohgahh

First strike, menace, trample
Partner (You can have two commanders if both have partner.)

Scab-Clan Berserker

Haste
Renown 1 (When this creature deals combat damage to a player, if it isn't renowned, put a +1/+1 counter on it and it becomes renowned.)
Whenever an opponent casts a noncreature spell, if Scab-Clan Berserker is renowned, Scab-Clan Berserker deals 2 damage to that player.

Plundering Barbarian

When Plundering Barbarian enters, choose one —
• Smash the Chest — Destroy target artifact.
• Pry It Open — Create a Treasure token. (It's an artifact with "{T}, Sacrifice this artifact: Add one mana of any color.")

Mountain

Hazoret's Monument

Red creature spells you cast cost {1} less to cast.
Whenever you cast a creature spell, you may discard a card. If you do, draw a card.

Battle Hymn

Dynacharge

Target creature you control gets +2/+0 until end of turn.
Overload {2}{R} (You may cast this spell for its overload cost. If you do, change "target" in its text to "each.")

Unexpected Windfall

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 artifact: Add one mana of any color.")

Neheb, Dreadhorde Champion

Trample
Whenever Neheb, Dreadhorde Champion deals combat damage to a player or planeswalker, you may discard any number of cards. If you do, draw that many cards and add that much {R}. Until end of turn, you don't lose this mana as steps and phases end.

Rage Reflection

Creatures you control have double strike.

Seize the Spoils

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

Neheb, the Eternal

Afflict 3 (Whenever this creature becomes blocked, defending player loses 3 life.)
At the beginning of your second main phase, add {R} for each 1 life your opponents have lost this turn.

Mizzium Mortars

Mizzium Mortars deals 4 damage to target creature you don't control.
Overload {3}{R}{R}{R} (You may cast this spell for its overload cost. If you do, change "target" in its text to "each.")

Manic Vandal

When Manic Vandal enters, destroy target artifact.

Lovisa Coldeyes

Each creature that's a Barbarian, a Warrior, or a Berserker gets +2/+2 and has haste.

Kolaghan Forerunners

Trample
Kolaghan Forerunners's power is equal to the number of creatures you control.
Dash {2}{R} (You may cast this spell for its dash cost. If you do, it gains haste, and it's returned from the battlefield to its owner's hand at the beginning of the next end step.)

Reckless Barbarian

Sacrifice Reckless Barbarian: Add {R}{R}.

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.

Wild Ricochet

You may choose new targets for target instant or sorcery spell. Then copy that spell. You may choose new targets for the copy.

Abrade

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

Aggravated Assault

{3}{R}{R}: Untap all creatures you control. After this main phase, there is an additional combat phase followed by an additional main phase. Activate only as a sorcery.

Horn of the Mark

Whenever two or more creatures you control attack a player, look at the top five cards of your library. You may reveal a creature card from among them and put it into your hand. Put the rest on the bottom of your library in a random order.

Demand Answers

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

Goblin Wardriver

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

Frontier Warmonger

Whenever one or more creatures attack one of your opponents or a planeswalker they control, those creatures gain menace until end of turn.

Kargan Intimidator

Cowards can't block Warriors.
{1}: Choose one that hasn't been chosen this turn —
• Kargan Intimidator gets +1/+1 until end of turn.
• Target creature becomes a Coward until end of turn.
• Target Warrior gains trample until end of turn.

Forgotten Cave

Forgotten Cave enters tapped.
{T}: Add {R}.
Cycling {R} ({R}, Discard this card: Draw a card.)

Fire Diamond

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

Bedlam

Fearless Liberator

Boast — {2}{R}: Create a 2/1 red Dwarf Berserker creature token. (Activate only if this creature attacked this turn and only once each turn.)

Gimli, Counter of Kills

Trample
Whenever a creature an opponent controls dies, Gimli, Counter of Kills deals 1 damage to that creature's controller.

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.)

Thrill of Possibility

Arcane Signet

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

Onslaught

Whenever you cast a creature spell, tap target creature.

Ghitu Encampment

Ghitu Encampment enters tapped.
{T}: Add {R}.
{1}{R}: Ghitu Encampment becomes a 2/1 red Warrior creature with first strike until end of turn. It's still a land. (It deals combat damage before creatures without first strike.)

Death-Greeter's Champion

Dash {3}{R} (You may cast this spell for its dash cost. If you do, it gains haste, and it's returned from the battlefield to its owner's hand at the beginning of the next end step.)
Backup 1 (When this creature enters, put a +1/+1 counter on target creature. If that's another creature, it gains the following ability until end of turn.)
Double strike

Archetype of Aggression

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

Hall of Triumph

As Hall of Triumph enters, choose a color.
Creatures you control of the chosen color get +1/+1.

Warlord's Fury

Creatures you control gain first strike until end of turn.
Draw a card.

Ogre Battledriver

Whenever another creature you control enters, that creature gets +2/+0 and gains haste until end of turn. (It can attack and {T} this turn.)