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.

Undead Gladiator

{1}{B}, Discard a card: Return Undead Gladiator from your graveyard to your hand. Activate only during your upkeep.
Cycling {1}{B} ({1}{B}, Discard this card: Draw a card.)

Tiger-Tribe Hunter

Trample
Pack tactics — Whenever Tiger-Tribe Hunter attacks, if you attacked with creatures with total power 6 or greater this combat, you may sacrifice another creature. When you do, Tiger-Tribe Hunter deals damage equal to the sacrificed creature's power to target creature.

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.)

Hoard Robber

Whenever Hoard Robber deals combat damage to a player, create a Treasure token. (It's an artifact with "{T}, Sacrifice this artifact: Add one mana of any color.")

Haunted One

Commander creatures you own have "Whenever this creature becomes tapped, it and other creatures you control that share a creature type with it each get +2/+0 and gain undying until end of turn." (When a creature with undying dies, if it had no +1/+1 counters on it, return it to the battlefield under its owner's control with a +1/+1 counter on it.)

Deadly Dispute

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

Possessed Barbarian

First strike
Threshold — As long as seven or more cards are in your graveyard, Possessed Barbarian gets +1/+1, is black, and has "{2}{B}, {T}: Destroy target red creature."

Read the Bones

Scry 2, then draw two cards. You lose 2 life. (To scry 2, look at the top two cards of your library, then put any number of them on the bottom and the rest on top in any order.)

Vicious Battlerager

When Vicious Battlerager enters, you take the initiative.
Spiked Retribution — Whenever Vicious Battlerager becomes blocked by a creature, that creature's controller loses 5 life.

Jeska, Warrior Adept

First strike, haste
{T}: Jeska, Warrior Adept deals 1 damage to any target.

Hell-Bent Raider

First strike, haste
Discard a card at random: Hell-Bent Raider gains protection from white until end of turn.

Taurean Mauler

Changeling (This card is every creature type.)
Whenever an opponent casts a spell, you may put a +1/+1 counter on this creature.

Guildsworn Prowler

Deathtouch
When Guildsworn Prowler dies, if it wasn't blocking, draw a card.

Zalto, Fire Giant Duke

Trample
Whenever Zalto, Fire Giant Duke is dealt damage, venture into the dungeon. (Enter the first room or advance to the next room.)

Passageway Seer

Lifelink
When Passageway Seer enters, you take the initiative.
At the beginning of your end step, if you have the initiative, put a +1/+1 counter on Passageway Seer.

Terminate

Destroy target creature. It can't be regenerated.

Bedevil

Destroy target artifact, creature, or planeswalker.

Blasphemous Act

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

Shared Animosity

Whenever a creature you control attacks, it gets +1/+0 until end of turn for each other attacking creature that shares a creature type with it.

Rising of the Day

Creatures you control have haste.
Legendary creatures you control get +1/+0.

Balthor the Stout

Other Barbarian creatures get +1/+1.
{R}: Another target Barbarian creature gets +1/+0 until end of turn.

Hobgoblin Captain

Pack tactics — Whenever Hobgoblin Captain attacks, if you attacked with creatures with total power 6 or greater this combat, Hobgoblin Captain gains first strike until end of turn.

Elturel Survivors

Trample, 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.)
As long as Elturel Survivors is attacking, it gets +X/+0, where X is the number of lands defending player controls.

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.

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.

Feed the Swarm

Destroy target creature or enchantment an opponent controls. You lose life equal to that permanent's mana value.

Rakdos Charm

Choose one —
• Exile target player's graveyard.
• Destroy target artifact.
• Each creature deals 1 damage to its controller.

Reckless Barbarian

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

Archetype of Aggression

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

Lovisa Coldeyes

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

Shivan Zombie

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.")

Corrupted Conviction

As an additional cost to cast this spell, sacrifice a creature.
Draw two cards.

Barbarian Riftcutter

{R}, Sacrifice Barbarian Riftcutter: Destroy target land.

Thrill of Possibility

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

Pardic Arsonist

Threshold — As long as seven or more cards are in your graveyard, Pardic Arsonist has "When Pardic Arsonist enters, it deals 3 damage to any target."

Night's Whisper

Pact of the Serpent

Choose a creature type. Target player draws X cards and loses X life, where X is the number of creatures they control of the chosen type.

Barbarian Outcast

When you control no Swamps, sacrifice Barbarian Outcast.

Village Rites

Sign in Blood

Target player draws two cards and loses 2 life.

Karlach, Fury of Avernus

Whenever you attack, if it's the first combat phase of the turn, untap all attacking creatures. They gain first strike until end of turn. After this phase, there is an additional combat phase.
Choose a Background (You can have a Background as a second commander.)

Keldon Champion

Haste
Echo {2}{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.)
When Keldon Champion enters, it deals 3 damage to target player or planeswalker.

Keldon Warlord

Keldon Warlord's power and toughness are each equal to the number of non-Wall creatures you control.

Kamahl, Pit Fighter

Haste (This creature can attack and {T} as soon as it comes under your control.)
{T}: Kamahl, Pit Fighter deals 3 damage to any target.

Barbarian Bully

Discard a card at random: Barbarian Bully gets +2/+2 until end of turn unless a player has Barbarian Bully deal 4 damage to them. Activate only once each turn.

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.

Victimize

Choose two target creature cards in your graveyard. Sacrifice a creature. If you do, return the chosen cards to the battlefield tapped.

Caves of Chaos Adventurer

Trample
When Caves of Chaos Adventurer enters, you take the initiative.
Whenever Caves of Chaos Adventurer attacks, exile the top card of your library. If you've completed a dungeon, you may play that card this turn without paying its mana cost. Otherwise, you may play that card this turn.

Changeling Outcast

Changeling (This card is every creature type.)
Changeling Outcast can't block and can't be blocked.

Valor Singer

Combat Inspiration — At the beginning of combat on your turn, target creature you control gets +1/+0 until end of turn.