Toxic Deluge

As an additional cost to cast this spell, pay X life.
All creatures get -X/-X until end of turn.

Golbez, Crystal Collector

Whenever an artifact you control enters, surveil 1.
At the beginning of your end step, if you control four or more artifacts, return target creature card from your graveyard to your hand. Then if you control eight or more artifacts, each opponent loses life equal to that card's power.

Colossus of Akros

Defender, indestructible
{10}: Monstrosity 10. (If this creature isn't monstrous, put ten +1/+1 counters on it and it becomes monstrous.)
As long as this creature is monstrous, it has trample and can attack as though it didn't have defender.

Sol Ring

Darksteel Juggernaut

Indestructible
Darksteel Juggernaut's power and toughness are each equal to the number of artifacts you control.
This creature attacks each combat if able.

Finale of Eternity

Destroy up to three target creatures with toughness X or less. If X is 10 or more, return all creature cards from your graveyard to the battlefield.

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.

Noble's Purse

This artifact enters tapped and with three coin counters on it.
{T}, Remove a coin counter from this artifact: Create a Treasure token. (It's an artifact with "{T}, Sacrifice this token: Add one mana of any color.")

Master of Etherium

Master of Etherium's power and toughness are each equal to the number of artifacts you control.
Other artifact creatures you control get +1/+1.

Tezzeret, Master of the Bridge

Creature and planeswalker spells you cast have affinity for artifacts. (They cost {1} less to cast for each artifact you control.)
+2: Tezzeret deals X damage to each opponent, where X is the number of artifacts you control. You gain X life.
−3: Return target artifact card from your graveyard to your hand.
−8: Exile the top ten cards of your library. Put all artifact cards from among them onto the battlefield.

Apocalypse Demon

Flying
Apocalypse Demon's power and toughness are each equal to the number of cards in your graveyard.
At the beginning of your upkeep, tap this creature unless you sacrifice another creature.

Thirst for Knowledge

Draw three cards. Then discard two cards unless you discard an artifact card.

Filigree Attendant

Flying
Filigree Attendant's power is equal to the number of artifacts you control.

Counterspell

Ancient Stone Idol

Flash
This spell costs {1} less to cast for each attacking creature.
Trample
When this creature dies, create a 6/12 colorless Construct artifact creature token with trample.

Urza, Lord High Artificer

When Urza enters, create a 0/0 colorless Construct artifact creature token with "This token 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.

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.

Thought Monitor

Affinity for artifacts (This spell costs {1} less to cast for each artifact you control.)
Flying
When this creature enters, draw two cards.

Matoya, Archon Elder

Whenever you scry or surveil, draw a card. (Draw after you scry or surveil.)

Arcane Signet

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

Thoughtcast

Affinity for artifacts (This spell costs {1} less to cast for each artifact you control.)
Draw two cards.

Armix, Filigree Thrasher

Whenever Armix 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.)

Mirrodin Besieged

As this enchantment enters, choose Mirran or Phyrexian.
• Mirran — Whenever you cast an artifact spell, create a 1/1 colorless Myr artifact creature token.
• Phyrexian — At the beginning of your end step, draw a card, then discard a card. Then if there are fifteen or more artifact cards in your graveyard, target opponent loses the game.

Chrome Host Seedshark

Flying
Whenever you cast a noncreature spell, incubate X, where X is that spell's mana value. (Create an Incubator token with X +1/+1 counters on it and "{2}: Transform this token." It transforms into a 0/0 Phyrexian artifact creature.)

Forensic Gadgeteer

Whenever you cast an artifact spell, investigate. (Create a Clue token. It's an artifact with "{2}, Sacrifice this token: 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.

Etherium Sculptor

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

Counterpoint

Counter target spell. You may cast a creature, instant, sorcery, or planeswalker spell from your graveyard with mana value less than or equal to that spell's mana value without paying its mana cost.

Emry, Lurker of the Loch

Affinity for artifacts (This spell costs {1} less to cast for each artifact you control.)
When Emry enters, mill four cards.
{T}: Choose target artifact card in your graveyard. You may cast that card this turn. (You still pay its costs. Timing rules still apply.)

Kappa Cannoneer

Improvise (Your artifacts can help cast this spell. Each artifact you tap after you're done activating mana abilities pays for {1}.)
Ward {4}
Whenever this creature or another artifact you control enters, put a +1/+1 counter on this creature. It can't be blocked this turn.

Countersquall

Counter target noncreature spell. Its controller loses 2 life.

Metalwork Colossus

This spell costs {X} less to cast, where X is the total mana value of noncreature artifacts you control.
Sacrifice two artifacts: Return this card from your graveyard to your hand.

Baleful Strix

Flying, deathtouch
When this creature enters, draw a card.

Riddlesmith

Whenever you cast an artifact spell, you may draw a card. If you do, discard a card.