Vessel of Volatility

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

Legion's Judgment

Destroy target creature with power 4 or greater.

Traverse the Outlands

Search your library for up to X basic land cards, where X is the greatest power among creatures you control. Put those cards onto the battlefield tapped, then shuffle.

Forktail Sweep

Forktail Sweep deals 1 damage to each creature you don't control. (Then exile this card. You may cast the creature later from exile.)

Fang Dragon

Fang Dragon // Forktail Sweep

Skanos Dragonheart

Whenever Skanos Dragonheart attacks, it gets +X/+X until end of turn, where X is the greatest power among other Dragons you control and Dragon cards in your graveyard.
Choose a Background (You can have a Background as a second commander.)

Incandescent Aria

Incandescent Aria deals 3 damage to each nontoken creature.

Universal Solvent

{7}, {T}, Sacrifice Universal Solvent: Destroy target permanent.

Explosive Crystal

Explosive Crystal deals 4 damage divided as you choose among any number of targets. (Then exile this card. You may cast the creature later from exile.)

Amethyst Dragon

Amethyst Dragon // Explosive Crystal

Rith, Liberated Primeval

Flying, ward {2}
Other Dragons you control have ward {2}.
At the beginning of your end step, if a creature or planeswalker an opponent controlled was dealt excess damage this turn, create a 4/4 red Dragon creature token with flying.

Breath Weapon

Breath Weapon deals 2 damage to each non-Dragon creature.

Racers' Ring

Racers' Ring enters tapped.
{T}: Add {R} or {G}.
{2}{R}{G}, {T}, Sacrifice Racers' Ring: Draw a card.

Involuntary Employment

Gain control of target creature until end of turn. Untap that creature. It gains haste until end of turn. Create a Treasure token. (It's an artifact with "{T}, Sacrifice this artifact: Add one mana of any color.")

Cliffgate

Cliffgate enters tapped.
As Cliffgate enters, choose a color other than red.
{T}: Add {R} or one mana of the chosen color.

Reckless Barbarian

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

Cathartic Reunion

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

Wooded Ridgeline

({T}: Add {R} or {G}.)
Wooded Ridgeline enters tapped.

Increasing Savagery

Put five +1/+1 counters on target creature. If this spell was cast from a graveyard, put ten +1/+1 counters on that creature instead.
Flashback {5}{G}{G} (You may cast this card from your graveyard for its flashback cost. Then exile it.)

Boon of Boseiju

Target creature gets +X/+X until end of turn, where X is the greatest mana value among permanents you control. Untap it.

Tyrant of Kher Ridges

Flying
When Tyrant of Kher Ridges enters, it deals 4 damage to any target.
{R}: Tyrant of Kher Ridges gets +1/+0 until end of turn.

Bhaal's Invoker

Scorching Ray — {8}: Bhaal's Invoker deals 4 damage to each opponent.

Ambitious Dragonborn

Ambitious Dragonborn enters with X +1/+1 counters on it, where X is the greatest power among creatures you control and creature cards in your graveyard.

Mountain

Bathe in Gold

Create a Treasure token. (Then exile this card. You may cast the creature later from exile.)

Young Red Dragon

Young Red Dragon // Bathe in Gold

Avenging Hunter

Trample
When Avenging Hunter enters, you take the initiative.

Valorous Stance

Choose one —
• Target creature gains indestructible until end of turn. (Damage and effects that say "destroy" don't destroy it.)
• Destroy target creature with toughness 4 or greater.

Marble Diamond

Marble Diamond enters tapped.
{T}: Add {W}.

Overwhelming Encounter

Creatures you control gain vigilance and trample until end of turn. Roll a d20.
1—9 | Creatures you control get +2/+2 until end of turn.
10—19 | Put two +1/+1 counters on each creature you control.
20 | Put four +1/+1 counters on each creature you control.

Scaled Nurturer

{T}: Add {G}. When you spend this mana to cast a Dragon creature spell, you gain 2 life.

King Darien XLVIII

Other creatures you control get +1/+1.
{3}{G}{W}: Put a +1/+1 counter on King Darien and create a 1/1 white Soldier creature token.
Sacrifice King Darien: Creature tokens you control gain hexproof and indestructible until end of turn.

Archivist of Oghma

Flash
Whenever an opponent searches their library, you gain 1 life and draw a card.

Dire Mimic

Flash
{T}, Sacrifice Dire Mimic: Add one mana of any color.
{3}: Dire Mimic becomes a Shapeshifter artifact creature with base power and toughness 5/5 until end of turn.

Forest

Crystal Grotto

When Crystal Grotto enters, scry 1.
{T}: Add {C}.
{1}, {T}: Add one mana of any color.

Scale Deflection

Put two +1/+1 counters on target creature and untap it. It gains hexproof until end of turn. (Then exile this card. You may cast the creature later from exile.)

Dread Linnorm

Dread Linnorm can't be blocked by creatures with power 3 or less.

Dread Linnorm // Scale Deflection

Glittering Stockpile

{T}: Add {R}. Put a stash counter on Glittering Stockpile.
{T}, Sacrifice Glittering Stockpile: Add X mana of any one color, where X is the number of stash counters on Glittering Stockpile.

Burn from Within

Burn from Within deals X damage to any target. If a creature is dealt damage this way, it loses indestructible until end of turn. If that creature would die this turn, exile it instead.

Radiant Grove

({T}: Add {G} or {W}.)
Radiant Grove enters tapped.

Poison the Blade

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

Manor Gate

Manor Gate enters tapped.
As Manor Gate enters, choose a color other than green.
{T}: Add {G} or one mana of the chosen color.

Owlbear Shepherd

At the beginning of your end step, if creatures you control have total power 8 or greater, draw a card.

Silvanus's Invoker

Conjure Elemental — {8}: Untap target land you control. It becomes an 8/8 Elemental creature with trample and haste until end of turn. It's still a land.

Plains

Patron of the Arts

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

Ancient Bronze Dragon

Flying
Whenever Ancient Bronze Dragon deals combat damage to a player, roll a d20. When you do, put X +1/+1 counters on each of up to two target creatures, where X is the result.

Bite Down

Target creature you control deals damage equal to its power to target creature or planeswalker you don't control.

Defiler of Faith

Vigilance
As an additional cost to cast white permanent spells, you may pay 2 life. Those spells cost {W} less to cast if you paid life this way. This effect reduces only the amount of white mana you pay.
Whenever you cast a white permanent spell, create a 1/1 white Soldier creature token.

Sacred Peaks

({T}: Add {R} or {W}.)
Sacred Peaks enters tapped.

Renegade Tactics

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

Master Chef

Commander creatures you own have "This creature enters with an additional +1/+1 counter on it" and "Other creatures you control enter with an additional +1/+1 counter on them."

Moss Diamond

Moss Diamond enters tapped.
{T}: Add {G}.

Dragon Whelp

Flying
{R}: Dragon Whelp gets +1/+0 until end of turn. If this ability has been activated four or more times this turn, sacrifice Dragon Whelp at the beginning of the next end step.

Vanquisher's Banner

As Vanquisher's Banner enters, choose a creature type.
Creatures you control of the chosen type get +1/+1.
Whenever you cast a creature spell of the chosen type, draw a card.

Selesnya Locket

{T}: Add {G} or {W}.
{G/W}{G/W}{G/W}{G/W}, {T}, Sacrifice Selesnya Locket: Draw two cards.

Lightning Bolt

Lightning Bolt deals 3 damage to any target.

Llanowar Loamspeaker

{T}: Add one mana of any color.
{T}: Target land you control becomes a 3/3 Elemental creature with haste until end of turn. It's still a land. Activate only as a sorcery.

Rakish Revelers

When Rakish Revelers enters, create a 1/1 green and white Citizen creature token.
{2}, Exile Rakish Revelers from your hand: Target land gains "{T}: Add {R}, {G}, or {W}" until Rakish Revelers is cast from exile. You may cast Rakish Revelers for as long as it remains exiled.

Carnelian Orb of Dragonkind

{T}: Add {R}. If that mana is spent on a Dragon creature spell, it gains haste until end of turn.

Herd Migration

Domain — Create a 3/3 green Beast creature token for each basic land type among lands you control.
{1}{G}, Discard Herd Migration: Search your library for a basic land card, reveal it, put it into your hand, then shuffle. You gain 3 life.

Jade Orb of Dragonkind

{T}: Add {G}. When you spend this mana to cast a Dragon creature spell, it enters with an additional +1/+1 counter on it and gains hexproof until your next turn. (It can't be the target of spells or abilities your opponents control.)

Shivan Meteor

Shivan Meteor deals 13 damage to target creature.
Suspend 2—{1}{R}{R} (Rather than cast this card from your hand, you may pay {1}{R}{R} and exile it with two time counters on it. At the beginning of your upkeep, remove a time counter. When the last is removed, you may cast it without paying its mana cost.)

Rending Flame

Rending Flame deals 5 damage to target creature or planeswalker. If that permanent is a Spirit, Rending Flame also deals 2 damage to that permanent's controller.

Botanical Plaza

Botanical Plaza enters tapped.
{T}: Add {G} or {W}.
{2}{G}{W}, {T}, Sacrifice Botanical Plaza: Draw a card.

Slaughter the Strong

Each player chooses any number of creatures they control with total power 4 or less, then sacrifices all other creatures they control.