Myr Retriever

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

Laboratory Maniac

If you would draw a card while your library has no cards in it, you win the game instead.

Seat of the Synod

Urza's Power Plant

{T}: Add {C}. If you control an Urza's Mine and an Urza's Tower, add {C}{C} instead.

Ashnod's Altar

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}.

Force of Will

You may pay 1 life and exile a blue card from your hand rather than pay this spell's mana cost.
Counter target spell.

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.

Force of Negation

If it's not your turn, you may exile a blue card from your hand rather than pay this spell's mana cost.
Counter target noncreature spell. If that spell is countered this way, exile it instead of putting it into its owner's graveyard.

Island

Welding Jar

Sacrifice Welding Jar: Regenerate target artifact.

Grand Architect

Other blue creatures you control get +1/+1.
{U}: Target artifact creature becomes blue until end of turn.
Tap an untapped blue creature you control: Add {C}{C}. Spend this mana only to cast artifact spells or activate abilities of artifacts.

Mana Crypt

At the beginning of your upkeep, flip a coin. If you lose the flip, Mana Crypt deals 3 damage to you.
{T}: Add {C}{C}.

Urza's Tower

{T}: Add {C}. If you control an Urza's Mine and an Urza's Power-Plant, add {C}{C}{C} instead.

Omniscience

You may cast spells from your hand without paying their mana costs.

Copy Artifact

You may have Copy Artifact enter as a copy of any artifact on the battlefield, except it's an enchantment in addition to its other types.

Urza's Mine

{T}: Add {C}. If you control an Urza's Power-Plant and an Urza's Tower, add {C}{C} instead.

Aetherflux Reservoir

Whenever you cast a spell, you gain 1 life for each spell you've cast this turn.
Pay 50 life: Aetherflux Reservoir deals 50 damage to any target.

Urza, Lord High Artificer

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

Pithing Needle

As Pithing Needle enters, choose a card name.
Activated abilities of sources with the chosen name can't be activated unless they're mana abilities.

Tolaria West

Tolaria West enters tapped.
{T}: Add {U}.
Transmute {1}{U}{U} ({1}{U}{U}, Discard this card: Search your library for a card with mana value 0, reveal it, put it into your hand, then shuffle. Transmute only as a sorcery.)

Mox Opal

Metalcraft — {T}: Add one mana of any color. Activate only if you control three or more artifacts.

Paradoxical Outcome

Return any number of target nonland, nontoken permanents you control to their owners' hands. Draw a card for each card returned to your hand this way.