Kenku Artificer

Homunculus Servant — When Kenku Artificer enters, put three +1/+1 counters on up to one target noncreature artifact. That artifact becomes a 0/0 Homunculus artifact creature with flying.

Nihil Spellbomb

{T}, Sacrifice Nihil Spellbomb: Exile target player's graveyard.
When Nihil Spellbomb is put into a graveyard from the battlefield, you may pay {B}. If you do, draw a card.

Metallic Rebuke

Improvise (Your artifacts can help cast this spell. Each artifact you tap after you're done activating mana abilities pays for {1}.)
Counter target spell unless its controller pays {3}.

Seat of the Synod

Chainer's Edict

Target player sacrifices a creature.
Flashback {5}{B}{B} (You may cast this card from your graveyard for its flashback cost. Then exile it.)

Hydroblast

Choose one —
• Counter target spell if it's red.
• Destroy target permanent if it's red.

Myr Enforcer

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

Krark-Clan Shaman

Sacrifice an artifact: Krark-Clan Shaman deals 1 damage to each creature without flying.

Gearseeker Serpent

This spell costs {1} less to cast for each artifact you control.
{5}{U}: Gearseeker Serpent can't be blocked this turn.

Silverbluff Bridge

Silverbluff Bridge enters tapped.
Indestructible
{T}: Add {U} or {R}.

Somber Hoverguard

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

Frogmite

Deadly Dispute

As an additional cost to cast this spell, sacrifice an artifact or creature.
Draw two cards and create a Treasure token. (It's an artifact with "{T}, Sacrifice this artifact: Add one mana of any color.")

Galvanic Blast

Galvanic Blast deals 2 damage to any target.
Metalcraft — Galvanic Blast deals 4 damage instead if you control three or more artifacts.

Pyroblast

Choose one —
• Counter target spell if it's blue.
• Destroy target permanent if it's blue.

Blood Fountain

When Blood Fountain enters, create a Blood token. (It's an artifact with "{1}, {T}, Discard a card, Sacrifice this artifact: Draw a card.")
{3}{B}, {T}, Sacrifice Blood Fountain: Return up to two target creature cards from your graveyard to your hand.

Reckoner's Bargain

As an additional cost to cast this spell, sacrifice an artifact or creature.
You gain life equal to the sacrificed permanent's mana value. Draw two cards.

Great Furnace

Gurmag Angler

Delve (Each card you exile from your graveyard while casting this spell pays for {1}.)

Drossforge Bridge

Drossforge Bridge enters tapped.
Indestructible
{T}: Add {B} or {R}.

Mistvault Bridge

Mistvault Bridge enters tapped.
Indestructible
{T}: Add {U} or {B}.

Thoughtcast

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

Vault of Whispers

Gorilla Shaman

{X}{X}{1}: Destroy target noncreature artifact with mana value X.

Chromatic Star

{1}, {T}, Sacrifice Chromatic Star: Add one mana of any color.
When Chromatic Star is put into a graveyard from the battlefield, draw a card.

Ichor Wellspring

When Ichor Wellspring enters or is put into a graveyard from the battlefield, draw a card.

Makeshift Munitions

{1}, Sacrifice an artifact or creature: Makeshift Munitions deals 1 damage to any target.