Torbran, Thane of Red Fell

If a red source you control would deal damage to an opponent or a permanent an opponent controls, it deals that much damage plus 2 instead.

Signal Pest

Battle cry (Whenever this creature attacks, each other attacking creature gets +1/+0 until end of turn.)
Signal Pest can't be blocked except by creatures with flying or reach.

Livaan, Cultist of Tiamat

Whenever you cast a noncreature spell, target creature gets +X/+0 until end of turn, where X is that spell's mana value.
Choose a Background (You can have a Background as a second commander.)

Devilish Valet

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

Hellrider

Haste
Whenever a creature you control attacks, Hellrider deals 1 damage to the player or planeswalker it's attacking.

Dragon Mantle

Enchant creature
When Dragon Mantle enters, draw a card.
Enchanted creature has "{R}: This creature gets +1/+0 until end of turn."

Brute Strength

Target creature gets +3/+1 and gains trample until end of turn. (It can deal excess combat damage to the player or planeswalker it's attacking.)

Subira, Tulzidi Caravanner

Haste
{1}: Another target creature with power 2 or less can't be blocked this turn.
{1}{R}, {T}, Discard your hand: Until end of turn, whenever a creature you control with power 2 or less deals combat damage to a player, draw a card.

Become Brutes

One or two target creatures each gain haste until end of turn. For each of those creatures, create a Monster Role token attached to it. (If you control another Role on it, put that one into the graveyard. Enchanted creature gets +1/+1 and has trample.)

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.)

Barge In

Target attacking creature gets +2/+2 until end of turn. Each attacking non-Human creature gains trample until end of turn.

Kindled Heroism

Target creature gets +1/+0 and gains first strike until end of turn. Scry 1.

Kobold Taskmaster

Other Kobold creatures you control get +1/+0.

Raze the Effigy

Choose one —
• Destroy target artifact.
• Target attacking creature gets +2/+2 until end of turn.

Sticky Fingers

Enchant creature
Enchanted creature has menace and "Whenever this creature deals combat damage to a player, create a Treasure token." (It can't be blocked except by two or more creatures. The token is an artifact with "{T}, Sacrifice this artifact: Add one mana of any color.")
When enchanted creature dies, draw a card.

Expedite

Target creature gains haste until end of turn.
Draw a card.

Titan's Strength

Target creature gets +3/+1 until end of turn. Scry 1. (Look at the top card of your library. You may put that card on the bottom.)

Crimson Wisps

Target creature becomes red and gains haste until end of turn. (It can attack and {T} this turn.)
Draw a card.

Kessig Flamebreather

Whenever you cast a noncreature spell, Kessig Flamebreather deals 1 damage to each opponent.

Storm-Kiln Artist

Storm-Kiln Artist gets +1/+0 for each artifact you control.
Magecraft — Whenever you cast or copy an instant or sorcery spell, create a Treasure token.

Mark of Fury

Enchant creature
Enchanted creature has haste.
At the beginning of the end step, return Mark of Fury to its owner's hand.

Heraldic Banner

As this artifact enters, choose a color.
Creatures you control of the chosen color get +1/+0.
{T}: Add one mana of the chosen color.

Guttersnipe

Whenever you cast an instant or sorcery spell, this creature deals 2 damage to each opponent.

Skullclamp

Equipped creature gets +1/-1.
Whenever equipped creature dies, draw two cards.
Equip {1}

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.")

Vindictive Flamestoker

Whenever you cast a noncreature spell, put an oil counter on Vindictive Flamestoker.
{6}{R}, Sacrifice Vindictive Flamestoker: Discard your hand, then draw four cards. This ability costs {1} less to activate for each oil counter on Vindictive Flamestoker.

Runaway Steam-Kin

Whenever you cast a red spell, if Runaway Steam-Kin has fewer than three +1/+1 counters on it, put a +1/+1 counter on Runaway Steam-Kin.
Remove three +1/+1 counters from Runaway Steam-Kin: Add {R}{R}{R}.

Impact Tremors

Whenever a creature you control enters, this enchantment deals 1 damage to each opponent.

Renegade Tactics

Target creature can't block this turn.
Draw a card.

Fists of Flame

Draw a card. Until end of turn, target creature gains trample and gets +1/+0 for each card you've drawn this turn. (A creature with trample can deal excess combat damage to the player or planeswalker it's attacking.)

Brute Force

Target creature gets +3/+3 until end of turn.

Harnfel, Horn of Bounty

Discard a card: Exile the top two cards of your library. You may play those cards this turn.

Birgi, God of Storytelling

Whenever you cast a spell, add {R}. Until end of turn, you don't lose this mana as steps and phases end.
Creatures you control can boast twice during each of your turns rather than once.

Birgi, God of Storytelling // Harnfel, Horn of Bounty

Battle Hymn

Sudden Breakthrough

Target creature gets +2/+0 and gains first strike until end of turn.
Create a Treasure token. (It's an artifact with "{T}, Sacrifice this artifact: Add one mana of any color.")

Dragon's Rage Channeler

Whenever you cast a noncreature spell, surveil 1. (Look at the top card of your library. You may put that card into your graveyard.)
Delirium — As long as there are four or more card types among cards in your graveyard, Dragon's Rage Channeler gets +2/+2, has flying, and attacks each combat if able.

Rosnakht, Heir of Rohgahh

Battle cry (Whenever this creature attacks, each other attacking creature gets +1/+0 until end of turn.)
Heroic — Whenever you cast a spell that targets Rosnakht, Heir of Rohgahh, create a 0/1 red Kobold creature token named Kobolds of Kher Keep.

Blazing Crescendo

Target creature gets +3/+1 until end of turn.
Exile the top card of your library. Until the end of your next turn, you may play that card.

Accelerate

Young Pyromancer

Whenever you cast an instant or sorcery spell, create a 1/1 red Elemental creature token.

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.")

Samut's Sprint

Target creature gets +2/+1 and gains haste until end of turn. Scry 1.

Goblin Wardriver

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

Witty Roastmaster

Alliance — Whenever another creature you control enters, Witty Roastmaster deals 1 damage to each opponent.

Firebrand Archer

Whenever you cast a noncreature spell, this creature deals 1 damage to each opponent.

Ancestral Anger

Target creature gains trample and gets +X/+0 until end of turn, where X is 1 plus the number of cards named Ancestral Anger in your graveyard. (A creature with trample can deal excess combat damage to the player or planeswalker it's attacking.)
Draw a card.