Toski, Bearer of Secrets

This spell can't be countered.
Indestructible
Toski, Bearer of Secrets attacks each combat if able.
Whenever a creature you control deals combat damage to a player, draw a card.

Ancient Cornucopia

Whenever you cast a spell that's one or more colors, you may gain 1 life for each of that spell's colors. Do this only once each turn.
{T}: Add one mana of any color.

Misleading Signpost

Flash
When Misleading Signpost enters during the declare attackers step, you may reselect which player or permanent target attacking creature is attacking. (It can't attack its controller or their permanents.)
{T}: Add {U}.

Thunderous Snapper

Whenever you cast a spell with mana value 5 or greater, draw a card.

Arcane Signet

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

Rapid Hybridization

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

Blinkmoth Urn

At the beginning of each player's first main phase, if Blinkmoth Urn is untapped, that player adds {C} for each artifact they control.

Emergence Zone

{T}: Add {C}.
{1}, {T}, Sacrifice Emergence Zone: You may cast spells this turn as though they had flash.

Swan Song

Counter target enchantment, instant, or sorcery spell. Its controller creates a 2/2 blue Bird creature token with flying.

Planar Nexus

Planar Nexus is every nonbasic land type. (Nonbasic land types include Cave, Desert, Gate, Lair, Locus, Mine, Power-Plant, Sphere, Tower, and Urza's.)
{T}: Add {C}.
{1}, {T}: Add one mana of any color.

Mishra's Workshop

{T}: Add {C}{C}{C}. Spend this mana only to cast artifact spells.

Thought Vessel

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

Cryptic Command

Choose two —
• Counter target spell.
• Return target permanent to its owner's hand.
• Tap all creatures your opponents control.
• Draw a card.

Encroaching Mycosynth

Nonland permanents you control are artifacts in addition to their other types. The same is true for permanent spells you control and nonland permanent cards you own that aren't on the battlefield.

Minamo, School at Water's Edge

{T}: Add {U}.
{U}, {T}: Untap target legendary permanent.

Strip Mine

{T}: Add {C}.
{T}, Sacrifice Strip Mine: Destroy target land.

Temple of the False God

{T}: Add {C}{C}. Activate only if you control five or more lands.

Mystic Remora

Cumulative upkeep {1} (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.)
Whenever an opponent casts a noncreature spell, you may draw a card unless that player pays {4}.

Null Elemental Blast

Choose one —
• Counter target multicolored spell.
• Destroy target multicolored permanent.

Sapphire Medallion

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

Disruption Protocol

As an additional cost to cast this spell, tap an untapped artifact you control or pay {1}.
Counter target spell.

Throne of Eldraine

As Throne of Eldraine enters, choose a color.
{T}: Add four mana of the chosen color. Spend this mana only to cast monocolored spells of that color.
{3}, {T}: Draw two cards. Spend only mana of the chosen color to activate this ability.

Urza, Lord High Artificer

When Urza, Lord High Artificer enters, create a 0/0 colorless Construct artifact creature token with "This creature gets +1/+1 for each artifact you control."
Tap an untapped artifact you control: Add {U}.
{5}: Shuffle your library, then exile the top card. Until end of turn, you may play that card without paying its mana cost.

River's Rebuke

Return all nonland permanents target player controls to their owner's hand.

Liquimetal Torque

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

Sai, Master Thopterist

Whenever you cast an artifact spell, create a 1/1 colorless Thopter artifact creature token with flying.
{1}{U}, Sacrifice two artifacts: Draw a card.

Negate

Worldwalker Helm

If you would create one or more artifact tokens, instead create those tokens plus an additional Map token. (It's an artifact with "{1}, {T}, Sacrifice this artifact: Target creature you control explores. Activate only as a sorcery.")
{1}{U}, {T}: Create a token that's a copy of target artifact token you control.

Forensic Gadgeteer

Whenever you cast an artifact spell, investigate. (Create a Clue token. It's an artifact with "{2}, Sacrifice this artifact: Draw a card.")
Activated abilities of artifacts you control cost {1} less to activate. This effect can't reduce the mana in that cost to less than one mana.

Midnight Clock

{T}: Add {U}.
{2}{U}: Put an hour counter on Midnight Clock.
At the beginning of each upkeep, put an hour counter on Midnight Clock.
When the twelfth hour counter is put on Midnight Clock, shuffle your hand and graveyard into your library, then draw seven cards. Exile Midnight Clock.

War Room

{T}: Add {C}.
{3}, {T}, Pay life equal to the number of colors in your commanders' color identity: Draw a card.

Tamiyo's Logbook

{5}{U}, {T}: Draw a card. This ability costs {1} less to activate for each other artifact you control.

Efficient Construction

Whenever you cast an artifact spell, create a 1/1 colorless Thopter artifact creature token with flying.

Sublime Epiphany

Choose one or more —
• Counter target spell.
• Counter target activated or triggered ability.
• Return target nonland permanent to its owner's hand.
• Create a token that's a copy of target creature you control.
• Target player draws a card.

Inventors' Fair

At the beginning of your upkeep, if you control three or more artifacts, you gain 1 life.
{T}: Add {C}.
{4}, {T}, Sacrifice Inventors' Fair: Search your library for an artifact card, reveal it, put it into your hand, then shuffle. Activate only if you control three or more artifacts.

Buried Ruin

{T}: Add {C}.
{2}, {T}, Sacrifice Buried Ruin: Return target artifact card from your graveyard to your hand.

Witching Well

When Witching Well enters, 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.)
{3}{U}, Sacrifice Witching Well: Draw two cards.

Flood of Tears

Return all nonland permanents to their owners' hands. If you return four or more nontoken permanents you control this way, you may put a permanent card from your hand onto the battlefield.

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.

Pongify

Destroy target creature. It can't be regenerated. Its controller creates a 3/3 green Ape creature token.

Urza's Factory

{T}: Add {C}.
{7}, {T}: Create a 2/2 colorless Assembly-Worker artifact creature token.

Prismatic Geoscope

Prismatic Geoscope enters tapped.
Domain — {T}: Add X mana in any combination of colors, where X is the number of basic land types among lands you control.

Scrapheap

Whenever an artifact or enchantment is put into your graveyard from the battlefield, you gain 1 life.

Otawara, Soaring City

{T}: Add {U}.
Channel — {3}{U}, Discard Otawara, Soaring City: Return target artifact, creature, enchantment, or planeswalker to its owner's hand. This ability costs {1} less to activate for each legendary creature you control.

Rings of Brighthearth

Whenever you activate an ability, if it isn't a mana ability, you may pay {2}. If you do, copy that ability. You may choose new targets for the copy.

Teferi's Ageless Insight

If you would draw a card except the first one you draw in each of your draw steps, draw two cards instead.

Fellwar Stone

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

Thran Dynamo

Jhoira's Familiar

Flying
Historic spells you cast cost {1} less to cast. (Artifacts, legendaries, and Sagas are historic.)

All Is Dust

Each player sacrifices all permanents they control that are one or more colors.

Golem's Heart

Whenever a player casts an artifact spell, you may gain 1 life.

Academy Ruins

{T}: Add {C}.
{1}{U}, {T}: Put target artifact card from your graveyard on top of your library.

Island

Beast Whisperer

Whenever you cast a creature spell, draw a card.

Stone of Erech

If a creature an opponent controls would die, exile it instead.
{2}, {T}, Sacrifice Stone of Erech: Exile target player's graveyard. Draw a card.

Simulacrum Synthesizer

When Simulacrum Synthesizer enters, scry 2.
Whenever another artifact you control with mana value 3 or greater enters, create a 0/0 colorless Construct artifact creature token with "This creature gets +1/+1 for each artifact you control."