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 this card from your graveyard.

Their Name Is Death

Kuldotha Forgemaster

{T}, Sacrifice three artifacts: Search your library for an artifact card, put it onto the battlefield, then shuffle.

Illuminor Szeras

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

Necron Monolith

Flying, indestructible
Eternity Gate — Whenever this Vehicle attacks, mill three cards. For each creature card milled this way, create a 2/2 black Necron Warrior artifact creature token.
Crew 4 (Tap any number of creatures you control with total power 4 or more: This Vehicle becomes an artifact creature until end of turn.)

Tomb Blade

Flying
Whenever this creature deals combat damage to a player, that player loses life equal to the number of creatures they control unless they sacrifice a creature of their choice.
Unearth {6}{B}{B}

Cabal Stronghold

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

Grave Pact

Whenever a creature you control dies, each other player sacrifices a creature of their choice.

Mask of Memory

Whenever equipped creature deals combat damage to a player, you may draw two cards. If you do, discard a card.
Equip {1} ({1}: Attach to target creature you control. Equip only as a sorcery.)

Vorpal Sword

Equipped creature gets +2/+0 and has deathtouch.
{5}{B}{B}{B}: Until end of turn, this Equipment gains "Whenever equipped creature deals combat damage to a player, that player loses the game."
Equip {B}{B}

Skeleton Shard

{3}, {T} or {B}, {T}: Return target artifact creature card from your graveyard to your hand.

Steel Overseer

{T}: Put a +1/+1 counter on each artifact creature you control.

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.

Cranial Plating

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

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.)

Triarch Praetorian

Flying
Dynastic Codes — When this creature enters from a graveyard, you draw two cards and you lose 2 life.
Unearth {4}{B} ({4}{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.)

Necron Deathmark

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

Canoptek Wraith

Wraith Form — This creature can't be blocked.
Transdimensional Scout — When this creature deals combat damage to a player, you may pay {3} and sacrifice it. If you do, choose a land you control. Then search your library for up to two basic land cards which have the same name as the chosen land, put them onto the battlefield tapped, then shuffle.

Phyrexian Triniform

When this creature dies, create three 3/3 colorless Phyrexian Golem artifact creature tokens.
Encore {12} ({12}, Exile this card from your graveyard: For each opponent, create a token copy that attacks that opponent this turn if able. They gain haste. Sacrifice them at the beginning of the next end step. Activate only as a sorcery.)

Darksteel Forge

Artifacts you control have indestructible. (Effects that say "destroy" don't destroy them. Artifact creatures with indestructible can't be destroyed by damage.)

Resurrection Orb

Equipped creature has lifelink.
Whenever equipped creature dies, return that card to the battlefield under its owner's control at the beginning of the next end step.
Equip {4} ({4}: Attach to target creature you control. Equip only as a sorcery.)

Cloud Key

As this artifact enters, choose artifact, creature, enchantment, instant, or sorcery.
Spells you cast of the chosen type cost {1} less to cast.

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.

Canoptek Tomb Sentinel

Vigilance
Exile Cannon — When this creature enters from a graveyard, exile up to one target nonland permanent.
Unearth {7} ({7}: 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.)

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.

Shard of the Nightbringer

Flying
Drain Life — When this creature enters, if you cast it, target opponent loses half their life, rounded up. You gain life equal to the life lost this way.

Leaden Myr

Reliquary Tower

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

Technomancer

When this creature 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.

Dread Return

Return target creature card from your graveyard to the battlefield.
Flashback—Sacrifice three creatures. (You may cast this card from your graveyard for its flashback cost. Then exile it.)

Lokhust Heavy Destroyer

Flying
Enmitic Exterminator — When this creature enters, each player sacrifices a creature of their choice.
Unearth {5}{B}{B}{B} ({5}{B}{B}{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.)

Scarecrone

{1}, Sacrifice a Scarecrow: Draw a card.
{4}, {T}: Return target artifact creature card from your graveyard to the battlefield.

Wayfarer's Bauble

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

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.

Black Sun's Twilight

Up to one target creature gets -X/-X until end of turn. If X is 5 or more, return a creature card with mana value X or less from your graveyard to the battlefield tapped.

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.

Tomb Fortress

This land enters tapped.
{T}: Add {B}.
{2}{B}{B}{B}, {T}, Exile this land: Mill four cards, then return a creature card from your graveyard to the battlefield. Activate only as a sorcery.

Damnation

Destroy all creatures. They can't be regenerated.

Entomb

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

Lychguard

Guardian Protocols — {3}{B}, Sacrifice this creature: Return all legendary creature cards from your graveyard to your hand.

Royal Warden

Phalanx Commander — When this creature enters, create two tapped 2/2 black Necron Warrior artifact creature tokens.
Unearth {3}{B} ({3}{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.)

Krark-Clan Ironworks

Shadow of the Enemy

Exile all creature cards from target player's graveyard. You may cast spells from among those cards for as long as they remain exiled, and mana of any type can be spent to cast them.

Nim Deathmantle

Equipped creature gets +2/+2, has intimidate, and is a black Zombie. (A creature with intimidate can't be blocked except by artifact creatures and/or creatures that share a color with it.)
Whenever a nontoken creature is put into your graveyard from the battlefield, you may pay {4}. If you do, return that card to the battlefield and attach this Equipment to it.
Equip {4}

Unwinding Clock

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

Cryptothrall

Protector — Other artifact creatures you control have hexproof.

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.

Plasmancer

Flying
Dynastic Advisor — When this creature enters, search your library for a basic Swamp card, reveal it, put it into your hand, then shuffle.

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.

Necron Overlord

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

Demonic Tutor

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

Sculpting Steel

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

Trazyn the Infinite

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

Darkness

Prevent all combat damage that would be dealt this turn.

Crucible of Worlds

Sensei's Divining Top

{1}: Look at the top three cards of your library, then put them back in any order.
{T}: Draw a card, then put this artifact on top of its owner's library.

Mutilate

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

Vat of Rebirth

Whenever another artifact or creature you control is put into a graveyard from the battlefield, put an oil counter on this artifact.
{2}{B}, {T}, Remove four oil counters from this artifact: Return target creature card from your graveyard to the battlefield. Activate only as a sorcery.

The War in Heaven

(As this Saga enters and after your draw step, add a lore counter. Sacrifice after III.)
I — You draw three cards and you lose 3 life.
II — Mill three cards.
III — Choose up to three target creature cards with total mana value 8 or less in your graveyard. Return each of them to the battlefield with a necrodermis counter on it. They're artifacts in addition to their other types.

Canoptek Spyder

Flying
Fabricator Claw Array — Whenever another nontoken artifact creature or Vehicle you control enters, draw a card.

Shard of the Void Dragon

Flying
Spear of the Void Dragon — Whenever this creature attacks, each opponent sacrifices a nonland permanent of their choice.
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 this creature.

Sol Ring

Swamp

Buried Ruin

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

Beacon of Unrest

Put target artifact or creature card from a graveyard onto the battlefield under your control. Shuffle Beacon of Unrest into its owner's library.

Cabal Coffers

{2}, {T}: Add {B} for each Swamp you control.

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.

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.

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.)

Vault of Whispers

Arcane Signet

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

Psychomancer

Flying
Harbinger of Despair — Whenever this creature 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.

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.