Carapace Forger

Metalcraft — This creature gets +2/+2 as long as you control three or more artifacts.

Negate

Gearseeker Serpent

Affinity for artifacts (This spell costs {1} less to cast for each artifact you control.)
{5}{U}: This creature can't be blocked this turn.

Mutagenic Growth

({G/P} can be paid with either {G} or 2 life.)
Target creature gets +2/+2 until end of turn.

Somber Hoverguard

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

Thoughtcast

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

Silverbluff Bridge

This land enters tapped.
Indestructible
{T}: Add {U} or {R}.

Tree of Tales

Cancel

Fling

As an additional cost to cast this spell, sacrifice a creature.
Fling deals damage equal to the sacrificed creature's power to any target.

Frogmite

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

Myr Enforcer

Steelfin Whale

Affinity for artifacts (This spell costs {1} less to cast for each artifact you control.)
Whenever an artifact you control enters, untap this creature.

Phyrexian Walker

Vault of Whispers

Mountain

Springleaf Drum

{T}, Tap an untapped creature you control: Add one mana of any color.

Temur Battle Rage

Target creature gains double strike until end of turn.
Ferocious — That creature also gains trample until end of turn if you control a creature with power 4 or greater.

Ornithopter

Mirran Mettle

Target creature gets +2/+2 until end of turn.
Metalcraft — That creature gets +4/+4 until end of turn instead if you control three or more artifacts.

Seat of the Synod

Island

Darksteel Citadel

Dispel

Great Furnace

Preordain

Scry 2, then draw a card. (To 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.)

Galvanic Blast

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

Swamp

Cast into the Fire

Choose one —
• Cast into the Fire deals 1 damage to each of up to two target creatures.
• Exile target artifact.

Stoic Rebuttal

Metalcraft — This spell costs {1} less to cast if you control three or more artifacts.
Counter target spell.

Slip Through Space

Devoid (This card has no color.)
Target creature can't be blocked this turn.
Draw a card.