Arcane Signet

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

No Witnesses

Each player who controls the most creatures investigates. Then destroy all creatures. (To investigate, create a Clue token. It's an artifact with "{2}, Sacrifice this artifact: Draw a card.")

Seething Song

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

Cleansing Nova

Choose one —
• Destroy all creatures.
• Destroy all artifacts and enchantments.

Talisman of Conviction

{T}: Add {C}.
{T}: Add {R} or {W}. Talisman of Conviction deals 1 damage to you.

Boompile

{T}: Flip a coin. If you win the flip, destroy all nonland permanents.

Akroma's Vengeance

Destroy all artifacts, creatures, and enchantments.
Cycling {3} ({3}, Discard this card: Draw a card.)

Preordain

Scry 2, then draw a card. (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.)

An Offer You Can't Refuse

Counter target noncreature spell. Its controller creates two Treasure tokens. (They're artifacts with "{T}, Sacrifice this artifact: Add one mana of any color.")

Blacksmith's Skill

Target permanent gains hexproof and indestructible until end of turn. If it's an artifact creature, it gets +2/+2 until end of turn.

Sublime Exhalation

Undaunted (This spell costs {1} less to cast for each opponent.)
Destroy all creatures.

Glacial Fortress

Glacial Fortress enters tapped unless you control a Plains or an Island.
{T}: Add {W} or {U}.

Guff Rewrites History

For each player, choose target nonenchantment, nonland permanent that player controls. Those permanents' owners shuffle them into their libraries. Each player who controlled one of those permanents exiles cards from the top of their library until they exile a nonland card, then puts the rest on the bottom of their library in a random order. Each player may cast the nonland card they exiled without paying its mana cost.

Path to Exile

Exile target creature. Its controller may search their library for a basic land card, put that card onto the battlefield tapped, then shuffle.

Serum Visions

Plains

Talisman of Creativity

{T}: Add {C}.
{T}: Add {U} or {R}. Talisman of Creativity deals 1 damage to you.

Rograkh, Son of Rohgahh

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

Sol Ring

Austere Command

Choose two —
• Destroy all artifacts.
• Destroy all enchantments.
• Destroy all creatures with mana value 3 or less.
• Destroy all creatures with mana value 4 or greater.

Urza's Sylex

{2}{W}{W}, {T}, Exile Urza's Sylex: Each player chooses six lands they control. Destroy all other permanents. Activate only as a sorcery.
When Urza's Sylex is put into exile from the battlefield, you may pay {2}. If you do, search your library for a planeswalker card, reveal it, put it into your hand, then shuffle.

Planar Cleansing

Volcanic Spite

Volcanic Spite deals 3 damage to target creature, planeswalker, or battle. You may put a card from your hand on the bottom of your library. If you do, draw a card.

Command Tower

Mana Geyser

Add {R} for each tapped land your opponents control.

Reality Scramble

Put target permanent you own on the bottom of your library. Reveal cards from the top of your library until you reveal a card that shares a card type with that permanent. Put that card onto the battlefield and the rest on the bottom of your library in a random order.
Retrace (You may cast this card from your graveyard by discarding a land card in addition to paying its other costs.)

Mystic Sanctuary

({T}: Add {U}.)
Mystic Sanctuary enters tapped unless you control three or more other Islands.
When Mystic Sanctuary enters untapped, you may put target instant or sorcery card from your graveyard on top of your library.

Terramorphic Expanse

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

Impulse

Look at the top four cards of your library. Put one of them into your hand and the rest on the bottom of your library in any order.

Mountain

Whirlwind of Thought

Whenever you cast a noncreature spell, draw a card.

Supreme Verdict

This spell can't be countered.
Destroy all creatures.

Fumigate

Destroy all creatures. You gain 1 life for each creature destroyed this way.

Hour of Revelation

This spell costs {3} less to cast if there are ten or more nonland permanents on the battlefield.
Destroy all nonland permanents.

Boros Signet

Dig Through Time

Delve (Each card you exile from your graveyard while casting this spell pays for {1}.)
Look at the top seven cards of your library. Put two of them into your hand and the rest on the bottom of your library in any order.

Day of Judgment

Skrelv's Hive

At the beginning of your upkeep, you lose 1 life and create a 1/1 colorless Phyrexian Mite artifact creature token with toxic 1 and "This creature can't block."
Corrupted — As long as an opponent has three or more poison counters, creatures you control with toxic have lifelink.

Reality Shift

Exile target creature. Its controller manifests the top card of their library. (That player puts the top card of their library onto the battlefield face down as a 2/2 creature. If it's a creature card, it can be turned face up any time for its mana cost.)

Catastrophe

Destroy all lands or all creatures. Creatures destroyed this way can't be regenerated.

Boros Garrison

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

Dovin's Veto

This spell can't be countered.
Counter target noncreature spell.

Treasure Cruise

Delve (Each card you exile from your graveyard while casting this spell pays for {1}.)
Draw three cards.

Adarkar Wastes

{T}: Add {C}.
{T}: Add {W} or {U}. Adarkar Wastes deals 1 damage to you.

Pyretic Ritual

Rapid Hybridization

Destroy target creature. It can't be regenerated. That creature's controller creates a 3/3 green Frog Lizard creature token.

Jeskai Ascendancy

Whenever you cast a noncreature spell, creatures you control get +1/+1 until end of turn. Untap those creatures.
Whenever you cast a noncreature spell, you may draw a card. If you do, discard a card.

Temple of Triumph

Temple of Triumph enters tapped.
When Temple of Triumph enters, scry 1.
{T}: Add {R} or {W}.

Mystic Monastery

Mystic Monastery enters tapped.
{T}: Add {U}, {R}, or {W}.

Prairie Stream

({T}: Add {W} or {U}.)
Prairie Stream enters tapped unless you control two or more basic lands.

Temple of Enlightenment

Temple of Enlightenment enters tapped.
When Temple of Enlightenment enters, scry 1.
{T}: Add {W} or {U}.

Frantic Search

Draw two cards, then discard two cards. Untap up to three lands.

Counterspell

Desperate Ritual

Add {R}{R}{R}.
Splice onto Arcane {1}{R} (As you cast an Arcane spell, you may reveal this card from your hand and pay its splice cost. If you do, add this card's effects to that spell.)

Exotic Orchard

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

Indomitable Creativity

Destroy X target artifacts and/or creatures. For each permanent destroyed this way, its controller reveals cards from the top of their library until an artifact or creature card is revealed and exiles that card. Those players put the exiled cards onto the battlefield, then shuffle.

Prismari Command

Choose two —
• Prismari Command deals 2 damage to any target.
• Target player draws two cards, then discards two cards.
• Target player creates a Treasure token.
• Destroy target artifact.

Skycloud Expanse

Ishai, Ojutai Dragonspeaker

Flying
Whenever an opponent casts a spell, put a +1/+1 counter on Ishai, Ojutai Dragonspeaker.
Partner (You can have two commanders if both have partner.)

Generous Gift

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

Polymorph

Destroy target creature. It can't be regenerated. Its controller reveals cards from the top of their library until they reveal a creature card. The player puts that card onto the battlefield, then shuffles all other cards revealed this way into their library.

Proteus Staff

{2}{U}, {T}: Put target creature on the bottom of its owner's library. That creature's controller reveals cards from the top of their library until they reveal a creature card. The player puts that card onto the battlefield and the rest on the bottom of their library in any order. Activate only as a sorcery.

Izzet Signet

Fated Retribution

Destroy all creatures and planeswalkers. If it's your turn, scry 2.

Avacyn, Angel of Hope

Flying, vigilance, indestructible
Other permanents you control have indestructible.

Azorius Signet

Fall of the Thran

(As this Saga enters and after your draw step, add a lore counter. Sacrifice after III.)
I — Destroy all lands.
II, III — Each player returns two land cards from their graveyard to the battlefield.

Chaos Mutation

Exile any number of target creatures controlled by different players. For each creature exiled this way, its controller reveals cards from the top of their library until they reveal a creature card, puts that card onto the battlefield, then puts the rest on the bottom of their library in a random order.

Mistveil Plains

({T}: Add {W}.)
Mistveil Plains enters tapped.
{W}, {T}: Put target card from your graveyard on the bottom of your library. Activate only if you control two or more white permanents.

Reliquary Tower

You have no maximum hand size.
{T}: Add {C}.

Ondu Skyruins

Ondu Skyruins enters tapped.
{T}: Add {W}.

Ondu Inversion

Ondu Inversion // Ondu Skyruins

Brainstorm

Draw three cards, then put two cards from your hand on top of your library in any order.

Armageddon

Worldslayer

Whenever equipped creature deals combat damage to a player, destroy all permanents other than Worldslayer.
Equip {5} ({5}: Attach to target creature you control. Equip only as a sorcery.)

Swords to Plowshares

Exile target creature. Its controller gains life equal to its power.

Mazemind Tome

{T}, Put a page counter on Mazemind Tome: Scry 1.
{2}, {T}, Put a page counter on Mazemind Tome: Draw a card.
When there are four or more page counters on Mazemind Tome, exile it. If you do, you gain 4 life.

Port Town

As Port Town enters, you may reveal a Plains or Island card from your hand. If you don't, Port Town enters tapped.
{T}: Add {W} or {U}.

Negate

Transmogrify

Exile target creature. That creature's controller reveals cards from the top of their library until they reveal a creature card. That player puts that card onto the battlefield, then shuffles the rest into their library.