Dictate of the Twin Gods

Flash
If a source would deal damage to a permanent or player, it deals double that damage to that permanent or player instead.

Caverns of Despair

No more than two creatures can attack each combat.
No more than two creatures can block each combat.

Excalibur, Sword of Eden

This spell costs {X} less to cast, where X is the total mana value of historic permanents you control. (Artifacts, legendaries, and Sagas are historic.)
Equipped creature gets +10/+0 and has vigilance.
Equip legendary creature {2}

Nykthos, Shrine to Nyx

{T}: Add {C}.
{2}, {T}: Choose a color. Add an amount of mana of that color equal to your devotion to that color. (Your devotion to a color is the number of mana symbols of that color in the mana costs of permanents you control.)

Witch's Clinic

{T}: Add {C}.
{2}, {T}: Target commander gains lifelink until end of turn.

Neheb, the Eternal

Afflict 3 (Whenever this creature becomes blocked, defending player loses 3 life.)
At the beginning of each of your postcombat main phases, add {R} for each 1 life your opponents have lost this turn.

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.

Talon Gates of Madara

When this land enters, up to one target creature phases out.
{T}: Add {C}.
{1}, {T}: Add one mana of any color.
{4}: Put this card from your hand onto the battlefield.

Fire Diamond

This artifact enters tapped.
{T}: Add {R}.

Mudslide

Creatures without flying don't untap during their controllers' untap steps.
At the beginning of each player's upkeep, that player may choose any number of tapped creatures without flying they control and pay {2} for each creature chosen this way. If the player does, untap those creatures.

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.

Simian Spirit Guide

Rite of Flame

Add {R}{R}, then add {R} for each card named Rite of Flame in each graveyard.

Arena of Glory

This land enters tapped unless you control a Mountain.
{T}: Add {R}.
{R}, {T}, Exert this land: Add {R}{R}. If that mana is spent on a creature spell, it gains haste until end of turn. (An exerted permanent won't untap during your next untap step.)

Null Brooch

{2}, {T}, Discard your hand: Counter target noncreature spell.

Forgotten Cave

This land enters tapped.
{T}: Add {R}.
Cycling {R} ({R}, Discard this card: Draw a card.)

Forbidden Orchard

{T}: Add one mana of any color.
Whenever you tap this land for mana, target opponent creates a 1/1 colorless Spirit creature token.

Varchild's War-Riders

Cumulative upkeep—Have an opponent create a 1/1 red Survivor creature token. (At the beginning of your upkeep, put an age counter on this permanent, then sacrifice it unless you pay its upkeep cost for each age counter on it.)
Trample; rampage 1 (Whenever this creature becomes blocked, it gets +1/+1 until end of turn for each creature blocking it beyond the first.)

Grafted Exoskeleton

Equipped creature gets +2/+2 and has infect. (It deals damage to creatures in the form of -1/-1 counters and to players in the form of poison counters.)
Whenever this Equipment becomes unattached from a permanent, sacrifice that permanent.
Equip {2}

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 token: Add one mana of any color.")

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.

Price of Progress

Price of Progress deals damage to each player equal to twice the number of nonbasic lands that player controls.

Pyretic Ritual

Big Score

Torpor Orb

Creatures entering don't cause abilities to trigger.

Treasonous Ogre

Dethrone (Whenever this creature attacks the player with the most life or tied for most life, put a +1/+1 counter on it.)
Pay 3 life: Add {R}.

Kratos, God of War

Double strike
All creatures have haste.
At the beginning of each player's end step, Kratos deals damage to that player equal to the number of creatures that player controls that didn't attack this turn.

Mjölnir, Storm Hammer

When Mjölnir enters, attach it to target legendary creature you control.
Whenever equipped creature attacks, tap target creature defending player controls and put a stun counter on it. Then Mjölnir deals damage to each opponent equal to the number of tapped creatures that opponent controls.
Equip {4}

Seize the Spotlight

Each opponent chooses fame or fortune. For each player who chose fame, gain control of a creature that player controls until end of turn. Untap those creatures and they gain haste until end of turn. For each player who chose fortune, you draw a card and create a Treasure token.

Screaming Nemesis

Haste
Whenever this creature is dealt damage, it deals that much damage to any other target. If a player is dealt damage this way, they can't gain life for the rest of the game.

Treasure Nabber

Whenever an opponent taps an artifact for mana, gain control of that artifact until the end of your next turn.

Blasphemous Act

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

Extraplanar Lens

Imprint — When this artifact enters, you may exile target land you control.
Whenever a land with the same name as the exiled card is tapped for mana, its controller adds one mana of any type that land produced.

Ragavan, Nimble Pilferer

Whenever Ragavan deals combat damage to a player, create a Treasure token and exile the top card of that player's library. Until end of turn, you may cast that card.
Dash {1}{R} (You may cast this spell for its dash cost. If you do, it gains haste, and it's returned from the battlefield to its owner's hand at the beginning of the next end step.)

Blood Moon

Arcane Signet

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

Magus of the Moon

Spider-Punk

Riot (This creature enters with your choice of a +1/+1 counter or haste.)
Other Spiders you control have riot.
Spells and abilities can't be countered.
Damage can't be prevented.

Liquimetal Torque

{T}: Add {C}.
{T}: Target nonland permanent becomes an artifact in addition to its other types until end of turn.

Varchild, Betrayer of Kjeldor

Whenever Varchild deals combat damage to a player, that player creates that many 1/1 red Survivor creature tokens.
Survivors your opponents control can't block, and they can't attack you or planeswalkers you control.
When Varchild leaves the battlefield, gain control of all Survivors.

Akroan Horse

Defender
When this creature enters, an opponent gains control of it.
At the beginning of your upkeep, each opponent creates a 1/1 white Soldier creature token.

Super State

Enchant creature you control
Enchanted creature has base power and toughness 9/9 and has flying, first strike, trample, and haste.
Whenever enchanted creature deals combat damage to an opponent, it deals that much damage to each other opponent.

Disrupt Decorum

Goad all creatures you don't control. (Until your next turn, those creatures attack each combat if able and attack a player other than you if able.)

Kediss, Emberclaw Familiar

Whenever a commander you control deals combat damage to an opponent, it deals that much damage to each other opponent.
Partner (You can have two commanders if both have partner.)

Uphill Battle

Creatures played by your opponents enter tapped.

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.)

Volcanic Fissure

As this land enters, you may pay 3 life. If you don't, it enters tapped.
{T}: Add {R}.

Sundering Eruption

Destroy target land. Its controller may search their library for a basic land card, put it onto the battlefield tapped, then shuffle. Creatures without flying can't block this turn.

Sundering Eruption // Volcanic Fissure

Crawlspace

No more than two creatures can attack you each combat.

Shadowspear

Equipped creature gets +1/+1 and has trample and lifelink.
{1}: Permanents your opponents control lose hexproof and indestructible until end of turn.
Equip {2}

Buster Sword

Equipped creature gets +3/+2.
Whenever equipped creature deals combat damage to a player, draw a card, then you may cast a spell from your hand with mana value less than or equal to that damage without paying its mana cost.
Equip {2}

Sol Ring

False Floor

This artifact enters tapped.
Creatures enter tapped.
{2}, {T}, Exile this artifact: Exile all untapped creatures. Activate only as a sorcery.

Solemn Simulacrum

When this creature enters, you may search your library for a basic land card, put that card onto the battlefield tapped, then shuffle.
When this creature dies, you may draw a card.

Hammer of Nazahn

Whenever Hammer of Nazahn or another Equipment you control enters, you may attach that Equipment to target creature you control.
Equipped creature gets +2/+0 and has indestructible.
Equip {4}

Snow-Covered Mountain

Ensnaring Bridge

Creatures with power greater than the number of cards in your hand can't attack.

Tibalt's Trickery

Counter target spell. Choose 1, 2, or 3 at random. Its controller mills that many cards, then exiles cards from the top of their library until they exile a nonland card with a different name than that spell. They may cast that card without paying its mana cost. Then they put the exiled cards on the bottom of their library in a random order.

Sword of the Animist

Equipped creature gets +1/+1.
Whenever equipped creature attacks, you may search your library for a basic land card, put it onto the battlefield tapped, then shuffle.
Equip {2}

Ornithopter of Paradise

Untimely Malfunction

Choose one —
• Destroy target artifact.
• Change the target of target spell or ability with a single target.
• One or two target creatures can't block this turn.

Silent Arbiter

No more than one creature can attack each combat.
No more than one creature can block each combat.

Smoke

Players can't untap more than one creature during their untap steps.

Mithril Coat

Flash
Indestructible
When Mithril Coat enters, attach it to target legendary creature you control.
Equipped creature has indestructible.
Equip {3}

Storage Matrix

As long as this artifact is untapped, each player chooses artifact, creature, or land during their untap step. That player can untap only permanents of the chosen type this step.

Valakut Stoneforge

Valakut Awakening

Put any number of cards from your hand on the bottom of your library, then draw that many cards plus one.

Valakut Awakening // Valakut Stoneforge

Loxodon Warhammer

Equipped creature gets +3/+0 and has trample and lifelink.
Equip {3}

Swiftfoot Boots

Equipped creature has hexproof and haste. (It can't be the target of spells or abilities your opponents control. It can attack and {T} no matter when it came under your control.)
Equip {1} ({1}: Attach to target creature you control. Equip only as a sorcery.)

Ruby Medallion

Red spells you cast cost {1} less to cast.

Wild Wasteland

Skip your draw step.
At the beginning of your upkeep, exile the top two cards of your library. You may play those cards this turn.

Valakut, the Molten Pinnacle

This land enters tapped.
Whenever a Mountain you control enters, if you control at least five other Mountains, you may have this land deal 3 damage to any target.
{T}: Add {R}.

Urabrask the Hidden

Creatures you control have haste.
Creatures your opponents control enter tapped.

Angel's Trumpet

All creatures have vigilance.
At the beginning of each player's end step, tap all untapped creatures that player controls that didn't attack this turn. This artifact deals damage to the player equal to the number of creatures tapped this way.

Arena of the Ancients

Legendary creatures don't untap during their controllers' untap steps.
When this artifact enters, tap all legendary creatures.

Gamble

Search your library for a card, put that card into your hand, discard a card at random, then shuffle.

Maze of Ith

{T}: Untap target attacking creature. Prevent all combat damage that would be dealt to and dealt by that creature this turn.