Sapphire Medallion

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

Spellskite

{U/P}: Change a target of target spell or ability to Spellskite. ({U/P} can be paid with either {U} or 2 life.)

Unwinding Clock

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

Sol Ring

Mycosynth Golem

Affinity for artifacts (This spell costs {1} less to cast for each artifact you control.)
Artifact creature spells you cast have affinity for artifacts. (They cost {1} less to cast for each artifact you control.)

Mana Vault

Mana Vault doesn't untap during your untap step.
At the beginning of your upkeep, you may pay {4}. If you do, untap Mana Vault.
At the beginning of your draw step, if Mana Vault is tapped, it deals 1 damage to you.
{T}: Add {C}{C}{C}.

Pristine Talisman

Mind Stone

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

Training Grounds

Activated abilities of creatures you control cost {2} less to activate. This effect can't reduce the mana in that cost to less than one mana.

Dramatic Reversal

Untap all nonland permanents you control.

Rhystic Study

Whenever an opponent casts a spell, you may draw a card unless that player pays {1}.

Cryptothrall

Protector — Other artifact creatures you control have hexproof.

Alloy Myr

Ornithopter of Paradise

Myr Retriever

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

Thought Monitor

Affinity for artifacts
Flying
When Thought Monitor enters, draw two cards.

Memnarch

{1}{U}{U}: Target permanent becomes an artifact in addition to its other types. (This effect lasts indefinitely.)
{3}{U}: Gain control of target artifact. (This effect lasts indefinitely.)

Arcane Signet

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

Mycosynth Lattice

All permanents are artifacts in addition to their other types.
All cards that aren't on the battlefield, spells, and permanents are colorless.
Players may spend mana as though it were mana of any color.

Palladium Myr

Silver Myr

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.

Shimmer Myr

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

Liquimetal Coating

{T}: Target permanent becomes an artifact in addition to its other types until end of turn.