Organic Extinction

Improvise (Your artifacts can help cast this spell. Each artifact you tap after you're done activating mana abilities pays for {1}.)
Destroy all nonartifact creatures.

Rakdos Signet

Iron Mastiff

Whenever Iron Mastiff attacks, roll a d20 for each player being attacked and ignore all but the highest roll.
1—9 | Iron Mastiff deals damage equal to its power to you.
10—19 | Iron Mastiff deals damage equal to its power to defending player.
20 | Iron Mastiff deals damage equal to its power to each opponent.

Xenosquirrels

Xenosquirrels enters with two +1/+1 counters on it.
After you roll a die, you may remove a +1/+1 counter from Xenosquirrels. If you do, increase or decrease the result by 1.

Cyberman Patrol

Artifact creatures you control have afflict 3. (Whenever a creature with afflict 3 becomes blocked, defending player loses 3 life.)

Plains

Boros Guildgate

This land enters tapped.
{T}: Add {R} or {W}.

Treasure Chest

{4}, Sacrifice Treasure Chest: Roll a d20.
1 | Trapped! — You lose 3 life.
2—9 | Create five Treasure tokens.
10—19 | You gain 3 life and draw three cards.
20 | Search your library for a card. If it's an artifact card, you may put it onto the battlefield. Otherwise, put that card into your hand. Then shuffle.

Costly Plunder

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

Tear

Destroy target enchantment.
Fuse (You may cast one or both halves of this card from your hand.)

Wear

Destroy target artifact.
Fuse (You may cast one or both halves of this card from your hand.)

Wear // Tear

Vault 21: House Gambit

(As this Saga enters and after your draw step, add a lore counter. Sacrifice after III.)
I, II — Discard a card, then draw a card.
III — Reveal up to five nonland cards from your hand. For each of those cards that has the same mana value as another card revealed this way, create a Treasure token.

Recruitment Drive

Roll a d20.
1—9 | Create two 1/1 white Soldier creature tokens.
10—19 | Create two 2/2 white Knight creature tokens.
20 | Create three 2/2 white Knight creature tokens.

Night Shift of the Living Dead

After you roll a die, you may pay 1 life. If you do, increase or decrease the result by 1. Do this only once each turn.
Whenever you roll a 6, create a 2/2 black Zombie Employee creature token.

Contraband Livestock

Exile target creature, then roll a d20.
1—9 | Its controller creates a 4/4 green Ox creature token.
10—19 | Its controller creates a 2/2 green Boar creature token.
20 | Its controller creates a 0/1 white Goat creature token.

Rakdos Guildgate

This land enters tapped.
{T}: Add {B} or {R}.

Orzhov Basilica

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

Strength-Testing Hammer

Whenever equipped creature attacks, roll a six-sided die. That creature gets +X/+0 until end of turn, where X is the result. Then if it has the greatest power or is tied for greatest power among creatures on the battlefield, draw a card.
Equip {3}

Attempted Murder

Choose target creature. Roll X six-sided dice. For each even result, put two -1/-1 counters on that creature. For each odd result, create a 1/2 blue Bird creature token with flying named Storm Crow.

Wyll's Reversal

Choose target spell or ability with one or more targets. Roll a d20 and add the greatest power among creatures you control.
1—14 | You may choose new targets for that spell or ability.
15+ | You may choose new targets for that spell or ability. Then copy it. You may choose new targets for the copy.

Myriad Landscape

Myriad Landscape enters tapped.
{T}: Add {C}.
{2}, {T}, Sacrifice Myriad Landscape: Search your library for up to two basic land cards that share a land type, put them onto the battlefield tapped, then shuffle.

Evolving Wilds

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

Boros Signet

Terramorphic Expanse

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

Farideh's Fireball

Farideh's Fireball deals 5 damage to target creature or planeswalker. Roll a d20.
1—9 | Farideh's Fireball deals 2 damage to each player.
10—20 | Farideh's Fireball deals 2 damage to each opponent.

Securitron Squadron

Squad {3} (As an additional cost to cast this spell, you may pay {3} any number of times. When this creature enters, create that many tokens that are copies of it.)
Vigilance
Whenever a creature token you control enters, put a +1/+1 counter on it.

Jan Jansen, Chaos Crafter

Haste
{T}, Sacrifice an artifact creature: Create two Treasure tokens.
{T}, Sacrifice a noncreature artifact: Create two 1/1 colorless Construct artifact creature tokens.

Chaos Dragon

Flying, haste
Chaos Dragon attacks each combat if able.
At the beginning of combat on your turn, each player rolls a d20. If one or more opponents had the highest result, Chaos Dragon can't attack those players or planeswalkers they control this combat.

Comet, Stellar Pup

0: Roll a six-sided die.
1 or 2 — [+2], then create two 1/1 green Squirrel creature tokens. They gain haste until end of turn.
3 — [−1], then return a card with mana value 2 or less from your graveyard to your hand.
4 or 5 — Comet, Stellar Pup deals damage equal to the number of loyalty counters on him to a creature or player, then [−2].
6 — [+1], and you may activate Comet, Stellar Pup's loyalty ability two more times this turn.

Clay Golem

{6}, Roll a d8: Monstrosity X, where X is the result. (If this creature isn't monstrous, put X +1/+1 counters on it and it becomes monstrous.)
Berserk — When Clay Golem becomes monstrous, destroy target permanent.

Rakdos Carnarium

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

Intangible Virtue

Creature tokens you control get +1/+1 and have vigilance.

Orzhov Guildgate

This land enters tapped.
{T}: Add {W} or {B}.

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.

Discerning Financier

At the beginning of your upkeep, if an opponent controls more lands than you, create a Treasure token. (It's an artifact with "{T}, Sacrifice this artifact: Add one mana of any color.")
{2}{W}: Choose another player. That player gains control of target Treasure you control. You draw a card.

Temple of Triumph

This land enters tapped.
When this land enters, scry 1. (Look at the top card of your library. You may put that card on the bottom.)
{T}: Add {R} or {W}.

Symmetry Matrix

Whenever a creature you control with power equal to its toughness enters, you may pay {1}. If you do, draw a card.

Brazen Dwarf

Whenever you roll one or more dice, Brazen Dwarf deals 1 damage to each opponent.

Monoxa, Midway Manager

Whenever you roll a 3 or higher, Monoxa, Midway Manager gains first strike until end of turn. If the roll was 4 or higher, it gains menace until end of turn. If the roll was 5 or higher, it gains lifelink until end of turn.
{6}: Roll a six-sided die.

Disciple of the Vault

Whenever an artifact is put into a graveyard from the battlefield, you may have target opponent lose 1 life.

Complaints Clerk

When Complaints Clerk enters, open an Attraction. (Put the top card of your Attraction deck onto the battlefield.)
Whenever you roll a 1, create a 1/1 white Clown Robot artifact creature token.

Mirkwood Bats

Flying
Whenever you create or sacrifice a token, each opponent loses 1 life.

Wand of Wonder

{4}, {T}: Roll a d20. Each opponent exiles cards from the top of their library until they exile an instant or sorcery card, then shuffles the rest into their library. You may cast up to X instant and/or sorcery spells from among cards exiled this way without paying their mana costs.
1—9 | X is one.
10—19 | X is two.
20 | X is three.

Exotic Orchard

{T}: Add one mana of any color that a land an opponent controls could produce.

Akoum Refuge

Akoum Refuge enters tapped.
When Akoum Refuge enters, you gain 1 life.
{T}: Add {B} or {R}.

Lightfoot Rogue

Sneak Attack — Whenever Lightfoot Rogue attacks, roll a d20.
1—9 | Lightfoot Rogue gains deathtouch until end of turn.
10—19 | It gets +1/+0 and gains deathtouch until end of turn.
20 | It gets +3/+0 and gains first strike and deathtouch until end of turn.

Arcane Signet

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

Component Pouch

{T}, Remove a component counter from Component Pouch: Add two mana of different colors.
{T}: Roll a d20.
1—9 | Put a component counter on Component Pouch.
10—20 | Put two component counters on Component Pouch.

Swarming Goblins

When Swarming Goblins enters, roll a d20.
1—9 | Create a 1/1 red Goblin creature token.
10—19 | Create two of those tokens.
20 | Create three of those tokens.

Valiant Endeavor

Roll two d6 and choose one result. Destroy each creature with power greater than or equal to that result. Then create a number of 2/2 white Knight creature tokens with vigilance equal to the other result.

Inspiring Leader

Commander creatures you own have "Creature tokens you control get +2/+2."

Command Tower

Generous Gift

Destroy target permanent. Its controller creates a 3/3 green Elephant creature token.

Bloodfell Caves

This land enters tapped.
When this land enters, you gain 1 life.
{T}: Add {B} or {R}.

Orzhov Signet

Clock of Omens

Tap two untapped artifacts you control: Untap target artifact.

Xorn

If you would create one or more Treasure tokens, instead create those tokens plus an additional Treasure token.

Mountain

Clowning Around

Create two 1/1 white Clown Robot artifact creature tokens, then roll a six-sided die. If the result is equal to or less than the number of Robots you control, create a 1/1 white Clown Robot artifact creature token.

Nothic

Weird Insight — When Nothic dies, roll a d20.
1—9 | You draw a card and you lose 1 life.
10—19 | You draw two cards and you lose 2 life.
20 | You draw seven cards and you lose 7 life.

Berserker's Frenzy

Cast this spell only before combat or during combat before blockers are declared.
Roll two d20 and ignore the lower roll.
1—14 | Choose any number of creatures. They block this turn if able.
15—20 | You choose which creatures block this turn and how those creatures block.

Losheel, Clockwork Scholar

Prevent all combat damage that would be dealt to attacking artifact creatures you control.
Whenever one or more artifact creatures you control enter, draw a card. This ability triggers only once each turn.

Idol of Oblivion

{T}: Draw a card. Activate only if you created a token this turn.
{8}, {T}, Sacrifice Idol of Oblivion: Create a 10/10 colorless Eldrazi creature token.

Smoldering Marsh

({T}: Add {B} or {R}.)
Smoldering Marsh enters tapped unless you control two or more basic lands.

Thopter Shop

Whenever one or more artifact creatures you control die, draw a card. This ability triggers only once each turn.
{2}{W}, {T}: Create a 1/1 colorless Thopter artifact creature token with flying.

Danse Macabre

Each player sacrifices a nontoken creature of their choice. Roll a d20 and add the toughness of the creature you sacrificed this way.
1—14 | Return a creature card put into a graveyard this way to the battlefield under your control.
15+ | Return up to two creature cards put into graveyards this way to the battlefield under your control.

Celebr-8000

At the beginning of combat on your turn, roll two six-sided dice. For each result of 1, Celebr-8000 gets +1/+1 until end of turn. For each other result, it gains the indicated ability until end of turn. If you rolled doubles, it also gains double strike until end of turn.
• 2 — menace
• 3 — vigilance
• 4 — lifelink
• 5 — flying
• 6 — indestructible

Temple of Malice

This land enters tapped.
When this land enters, scry 1. (Look at the top card of your library. You may put that card on the bottom.)
{T}: Add {B} or {R}.

Nomad Outpost

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

Wyll, Blade of Frontiers

If you would roll one or more dice, instead roll that many dice plus one and ignore the lowest roll.
Whenever you roll one or more dice, put a +1/+1 counter on Wyll, Blade of Frontiers.
Choose a Background (You can have a Background as a second commander.)

Mr. House, President and CEO

Whenever you roll a 4 or higher, create a 3/3 colorless Robot artifact creature token. If you rolled 6 or higher, instead create that token and a Treasure token.
{4}, {T}: Roll a six-sided die plus an additional six-sided die for each mana from Treasures spent to activate this ability.

Barbarian Class

(Gain the next level as a sorcery to add its ability.)
If you would roll one or more dice, instead roll that many dice plus one and ignore the lowest roll.
{1}{R}: Level 2
Whenever you roll one or more dice, target creature you control gets +2/+0 and gains menace until end of turn.
{2}{R}: Level 3
Creatures you control have haste.

Priority Boarding

Whenever you roll a die, you may reveal the top card of your library. Do this only once each turn. Whenever you reveal a card with mana value less than the result this way, you may exile it. If you do, you may play it this turn.

Wind-Scarred Crag

This land enters tapped.
When this land enters, you gain 1 life.
{T}: Add {R} or {W}.

Myrkul's Edict

Roll a d20.
1—9 | Choose an opponent. That player sacrifices a creature of their choice.
10—19 | Each opponent sacrifices a creature of their choice.
20 | Each opponent sacrifices a creature with the greatest power among creatures that player controls.

Prosperous Partnership

When Prosperous Partnership enters, create two 1/1 green and white Citizen creature tokens.
Tap three untapped creatures you control: Create a Treasure token.

Grave Endeavor

Roll two d10 and choose one result. Return a creature card from your graveyard to the battlefield with a number of +1/+1 counters on it equal to that result. Then each opponent loses X life and you gain X life, where X is the other result.

Swamp

Revivify

Roll a d20 and add the number of creature cards in your graveyard that were put there from the battlefield this turn.
1—14 | Return all creature cards in your graveyard that were put there from the battlefield this turn to your hand.
15+ | Return those cards from your graveyard to the battlefield.

Temple of Silence

This land enters tapped.
When this land enters, scry 1. (Look at the top card of your library. You may put that card on the bottom.)
{T}: Add {W} or {B}.

Spiked Pit Trap

Flash
{5}, {T}, Sacrifice Spiked Pit Trap: Choose target creature, then roll a d20.
1—9 | Spiked Pit Trap deals 5 damage to that creature.
10—20 | Spiked Pit Trap deals 5 damage to that creature. Create a Treasure token.

The Deck of Many Things

{2}, {T}: Roll a d20 and subtract the number of cards in your hand. If the result is 0 or less, discard your hand.
1—9 | Return a card at random from your graveyard to your hand.
10—19 | Draw two cards.
20 | Put a creature card from any graveyard onto the battlefield under your control. When that creature dies, its owner loses the game.

Vexing Puzzlebox

Whenever you roll one or more dice, put a number of charge counters on Vexing Puzzlebox equal to the result.
{T}: Add one mana of any color. Roll a d20.
{T}, Remove 100 charge counters from Vexing Puzzlebox: Search your library for an artifact card, put that card onto the battlefield, then shuffle.

Hoarding Ogre

Whenever Hoarding Ogre attacks, roll a d20.
1—9 | Create a Treasure token. (It's an artifact with "{T}, Sacrifice this artifact: Add one mana of any color.")
10—19 | Create two Treasure tokens.
20 | Create three Treasure tokens.

Boros Garrison

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

Scoured Barrens

This land enters tapped.
When this land enters, you gain 1 life.
{T}: Add {W} or {B}.

Thunderwave

Roll a d20.
1—9 | Thunderwave deals 3 damage to each creature.
10—19 | You may choose a creature. Thunderwave deals 3 damage to each creature not chosen this way.
20 | Thunderwave deals 6 damage to each creature your opponents control.

Circuits Act

Roll three six-sided dice. For each different result, create a 1/1 white Clown Robot artifact creature token.

Six-Sided Die

Choose target creature. Roll a six-sided die.
1 — It has base toughness 1 until end of turn.
2 — Put two -1/-1 counters on it.
3 — Six-Sided Die deals 3 damage to it and you gain 3 life.
4 — It gets -4/-4 until end of turn.
5 — Destroy it.
6 — Exile it.

Chaos Channeler

Wild Magic Surge — Whenever Chaos Channeler attacks, roll a d20.
1—9 | Exile the top card of your library. You may play it this turn.
10—19 | Exile the top two cards of your library. You may play them this turn.
20 | Exile the top three cards of your library. You may play them this turn.