Go for the Throat

The Core

(Transforms from Matzalantli.)
Fathomless descent — {T}: Add X mana of any one color, where X is the number of permanent cards in your graveyard.

Matzalantli, the Great Door

{T}: Draw a card, then discard a card.
{4}, {T}: Transform Matzalantli, the Great Door. Activate only if there are four or more permanent types among cards in your graveyard. (Artifact, battle, creature, enchantment, land, and planeswalker are permanent types.)

Matzalantli, the Great Door // The Core

Palladium Myr

Dark Ritual

Entomb

Search your library for a card, put that card into your graveyard, then shuffle.

Arcane Signet

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

Biotransference

Creatures you control are artifacts in addition to their other types. The same is true for creature spells you control and creature cards you own that aren't on the battlefield.
Whenever you cast an artifact spell, you lose 1 life and create a 2/2 black Necron Warrior artifact creature token.

Swiftfoot Boots

Equipped creature has hexproof and haste. (It can't be the target of spells or abilities your opponents control.)
Equip {1}

Cranial Plating

Equipped creature gets +1/+0 for each artifact you control.
{B}{B}: Attach Cranial Plating to target creature you control.
Equip {1}

Trazyn the Infinite

Deathtouch
Prismatic Gallery — As long as Trazyn the Infinite is on the battlefield, it has all activated abilities of all artifact cards in your graveyard.

Sculpting Steel

You may have Sculpting Steel enter as a copy of any artifact on the battlefield.

Living Death

Each player exiles all creature cards from their graveyard, then sacrifices all creatures they control, then puts all cards they exiled this way onto the battlefield.

Thought Vessel

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

Out of the Tombs

At the beginning of your upkeep, put two eon counters on Out of the Tombs, then mill cards equal to the number of eon counters on it.
If you would draw a card while your library has no cards in it, instead return a creature card from your graveyard to the battlefield. If you can't, you lose the game.

Disciples of Gix

When Disciples of Gix enters, search your library for up to three artifact cards, put them into your graveyard, then shuffle.

Shimmer Myr

Flash
You may cast artifact spells as though they had flash.

Cryptek

{1}{B}, {T}: Choose another target artifact creature you control. When that creature dies this turn, return it to the battlefield tapped under your control.

Mirage Mirror

{2}: Mirage Mirror becomes a copy of target artifact, creature, enchantment, or land until end of turn.

Swamp

Technomancer

When Technomancer enters, mill three cards, then return any number of artifact creature cards with total mana value 6 or less from your graveyard to the battlefield.

Staff of Nin

At the beginning of your upkeep, draw a card.
{T}: Staff of Nin deals 1 damage to any target.

Unmarked Grave

Search your library for a nonlegendary card, put that card into your graveyard, then shuffle.

Mutilate

All creatures get -1/-1 until end of turn for each Swamp you control.

Buried Ruin

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

Bolas's Citadel

You may look at the top card of your library any time.
You may play lands and cast spells from the top of your library. If you cast a spell this way, pay life equal to its mana value rather than pay its mana cost.
{T}, Sacrifice ten nonland permanents: Each opponent loses 10 life.

Cyberman Patrol

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

Voltaic Construct

Vault of Whispers

Insatiable Avarice

Spree (Choose one or more additional costs.)
+ {2} — Search your library for a card, then shuffle and put that card on top.
+ {B}{B} — Target player draws three cards and loses 3 life.

Cryptothrall

Protector — Other artifact creatures you control have hexproof.

Skorpekh Lord

Menace
Command Protocols — Other artifact creatures you control get +1/+0 and have menace.
Unearth {2}{B} ({2}{B}: Return this card from your graveyard to the battlefield. It gains haste. Exile it at the beginning of the next end step or if it would leave the battlefield. Unearth only as a sorcery.)

Unseal the Necropolis

Each player mills three cards. Then you return up to two creature cards from your graveyard to your hand. (To mill three cards, a player puts the top three cards of their library into their graveyard.)

Millikin

{T}, Mill a card: Add {C}. (To mill a card, put the top card of your library into your graveyard.)

Karn, Legacy Reforged

Karn, Legacy Reforged's power and toughness are each equal to the greatest mana value among artifacts you control.
At the beginning of your upkeep, add {C} for each artifact you control. This mana can't be spent to cast nonartifact spells. Until end of turn, you don't lose this mana as steps and phases end.

Shard of the Void Dragon

Flying
Spear of the Void Dragon — Whenever Shard of the Void Dragon attacks, each opponent sacrifices a nonland permanent.
Matter Absorption — Whenever an artifact is put into a graveyard from the battlefield or is put into exile from the battlefield, put two +1/+1 counters on Shard of the Void Dragon.

Myr Retriever

When Myr Retriever dies, return another target artifact card from your graveyard to your hand.

Gilded Lotus

Darkness

Prevent all combat damage that would be dealt this turn.

Thran Dynamo

Necron Deathmark

Flash
Synaptic Disintegrator — When Necron Deathmark enters, destroy up to one target creature and target player mills three cards.

Anrakyr the Traveller

Lord of the Pyrrhian Legions — Whenever Anrakyr the Traveller attacks, you may cast an artifact spell from your hand or graveyard by paying life equal to its mana value rather than paying its mana cost.

Monumental Corruption

Target player draws X cards and loses X life, where X is the number of artifacts you control.

Vile Entomber

Deathtouch
When Vile Entomber enters, search your library for a card, put that card into your graveyard, then shuffle.

Darksteel Citadel

Codex Shredder

{T}: Target player mills a card. (They put the top card of their library into their graveyard.)
{5}, {T}, Sacrifice Codex Shredder: Return target card from your graveyard to your hand.

Phyrexian Scriptures

(As this Saga enters and after your draw step, add a lore counter. Sacrifice after III.)
I — Put a +1/+1 counter on up to one target creature. That creature becomes an artifact in addition to its other types.
II — Destroy all nonartifact creatures.
III — Exile all opponents' graveyards.

Oriq Loremage

{T}: Search your library for a card, put it into your graveyard, then shuffle. If it's an instant or sorcery card, put a +1/+1 counter on Oriq Loremage.

Cemetery Tampering

Hideaway 5 (When this enchantment enters, look at the top five cards of your library, exile one face down, then put the rest on the bottom in a random order.)
At the beginning of your upkeep, you may mill three cards. Then if there are twenty or more cards in your graveyard, you may play the exiled card without paying its mana cost.

Bitter Triumph

As an additional cost to cast this spell, discard a card or pay 3 life.
Destroy target creature or planeswalker.

Imotekh the Stormlord

Phaeron — Whenever one or more artifact cards leave your graveyard, create two 2/2 black Necron Warrior artifact creature tokens.
Grand Strategist — At the beginning of combat on your turn, another target artifact creature you control gets +2/+2 and gains menace until end of turn.

Sol Ring

Their Name Is Death

Ransack the Lab

Look at the top three cards of your library. Put one of them into your hand and the rest into your graveyard.

Pili-Pala

Flying
{2}, {Q}: Add one mana of any color. ({Q} is the untap symbol.)

Lightning Greaves

Equipped creature has haste and shroud. (It can't be the target of spells or abilities.)
Equip {0}

Nyx Lotus

Nyx Lotus enters tapped.
{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.)

Hedron Archive

{T}: Add {C}{C}.
{2}, {T}, Sacrifice Hedron Archive: Draw two cards.

Mystic Forge

You may look at the top card of your library any time.
You may cast artifact spells and colorless spells from the top of your library.
{T}, Pay 1 life: Exile the top card of your library.

Feed the Swarm

Destroy target creature or enchantment an opponent controls. You lose life equal to that permanent's mana value.

Convergence of Dominion

Dynastic Command Node — As long as you control your commander, activated abilities of cards in your graveyard cost {2} less to activate. This effect can't reduce the mana in that ability's activation cost to less than one mana.
Translocation Protocols — {3}, {T}: Mill three cards.

Triskelion

Triskelion enters with three +1/+1 counters on it.
Remove a +1/+1 counter from Triskelion: It deals 1 damage to any target.

Foundry Inspector

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

Mind Stone

{T}: Add {C}.
{1}, {T}, Sacrifice Mind Stone: Draw a card.

Golem Artisan

{2}: Target artifact creature gets +1/+1 until end of turn.
{2}: Target artifact creature gains your choice of flying, trample, or haste until end of turn.

Jet Medallion

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

Perpetual Timepiece

{T}: Mill two cards.
{2}, Exile Perpetual Timepiece: Shuffle any number of target cards from your graveyard into your library.

Psychomancer

Flying
Harbinger of Despair — Whenever Psychomancer or another nontoken artifact you control is put into a graveyard from the battlefield or is put into exile from the battlefield, target opponent loses 1 life and you gain 1 life.

Necron Overlord

Relentless March — {X}, {T}, Tap X untapped artifacts you control: Target opponent loses X life.

Phyrexian Devourer

When Phyrexian Devourer's power is 7 or greater, sacrifice it.
Exile the top card of your library: Put X +1/+1 counters on Phyrexian Devourer, where X is the exiled card's mana value.

Necrotic Ooze

As long as Necrotic Ooze is on the battlefield, it has all activated abilities of all creature cards in all graveyards.

Walking Ballista

Walking Ballista enters with X +1/+1 counters on it.
{4}: Put a +1/+1 counter on Walking Ballista.
Remove a +1/+1 counter from Walking Ballista: It deals 1 damage to any target.

Illuminor Szeras

Secrets of the Soul — {T}, Sacrifice another creature: Add an amount of {B} equal to the sacrificed creature's mana value.

Damnation

Destroy all creatures. They can't be regenerated.

Palantír of Orthanc

At the beginning of your end step, put an influence counter on Palantír of Orthanc and scry 2. Then target opponent may have you draw a card. If that player doesn't, you mill X cards, where X is the number of influence counters on Palantír of Orthanc, and that player loses life equal to the total mana value of those cards.

Defile

Target creature gets -1/-1 until end of turn for each Swamp you control.

Szarekh, the Silent King

Flying
My Will Be Done — Whenever Szarekh, the Silent King attacks, mill three cards. You may put an artifact creature card or Vehicle card from among the cards milled this way into your hand.

Unstable Obelisk

{T}: Add {C}.
{7}, {T}, Sacrifice Unstable Obelisk: Destroy target permanent.

Annihilating Glare

As an additional cost to cast this spell, pay {4} or sacrifice an artifact or creature.
Destroy target creature or planeswalker.

Funeral Rites

You draw two cards, lose 2 life, then mill two cards.

Armix, Filigree Thrasher

Whenever Armix, Filigree Thrasher attacks, you may discard a card. When you do, target creature defending player controls gets -X/-X until end of turn, where X is the number of artifacts you control plus the number of artifact cards in your graveyard.
Partner (You can have two commanders if both have partner.)

Unwinding Clock

Untap all artifacts you control during each other player's untap step.

Flayed One

Lifelink
Flesh Flayer — When Flayed One enters, mill three cards.

Staff of Compleation

{T}, Pay 1 life: Destroy target permanent you own.
{T}, Pay 2 life: Add one mana of any color.
{T}, Pay 3 life: Proliferate.
{T}, Pay 4 life: Draw a card.
{5}: Untap Staff of Compleation.

Chronomancer

Flying
Atomic Transmutation — {1}, {T}, Sacrifice another artifact: Draw a card.
Unearth {2}{B} ({2}{B}: Return this card from your graveyard to the battlefield. It gains haste. Exile it at the beginning of the next end step or if it would leave the battlefield. Unearth only as a sorcery.)

Cabal Stronghold

{T}: Add {C}.
{3}, {T}: Add {B} for each basic Swamp you control.

Their Number Is Legion

Create X tapped 2/2 black Necron Warrior artifact creature tokens, then you gain life equal to the number of artifacts you control. Exile Their Number Is Legion.
You may cast Their Number Is Legion from your graveyard.

Mirrorworks

Whenever another nontoken artifact you control enters, you may pay {2}. If you do, create a token that's a copy of that artifact.

Buried Alive

Search your library for up to three creature cards, put them into your graveyard, then shuffle.

Staff of Domination

{1}: Untap Staff of Domination.
{2}, {T}: You gain 1 life.
{3}, {T}: Untap target creature.
{4}, {T}: Tap target creature.
{5}, {T}: Draw a card.

Stitcher's Supplier

When Stitcher's Supplier enters or dies, mill three cards. (Put the top three cards of your library into your graveyard.)

Farmstead Gleaner

Farmstead Gleaner doesn't untap during your untap step.
{2}, {Q}: Put a +1/+1 counter on Farmstead Gleaner. ({Q} is the untap symbol.)

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.

Caged Sun

As Caged Sun enters, choose a color.
Creatures you control of the chosen color get +1/+1.
Whenever a land's ability causes you to add one or more mana of the chosen color, add one additional mana of that color.

Sceptre of Eternal Glory

{T}: Add one mana of any color.
{T}: Add three mana of any one color. Activate only if you control three or more lands with the same name.

Bojuka Bog

Bojuka Bog enters tapped.
When Bojuka Bog enters, exile target player's graveyard.
{T}: Add {B}.