Voltaic Key

Cloud Key

As Cloud Key enters, choose artifact, creature, enchantment, instant, or sorcery.
Spells you cast of the chosen type cost {1} less to cast.

Coldsteel Heart

Coldsteel Heart enters tapped.
As Coldsteel Heart enters, choose a color.
{T}: Add one mana of the chosen color.

Ysgard's Call

Create X 1/1 white Soldier creature tokens. (Then exile this card. You may cast the artifact later from exile.)

Horn of Valhalla

Equipped creature gets +1/+1 for each creature you control.
Equip {3}

Horn of Valhalla // Ysgard's Call

Amareth, the Lustrous

Flying
Whenever another permanent you control enters, look at the top card of your library. If it shares a card type with that permanent, you may reveal that card and put it into your hand.

Mangara's Tome

When Mangara's Tome enters, search your library for five cards, exile them in a face-down pile, and shuffle that pile. Then shuffle your library.
{2}: The next time you would draw a card this turn, instead put the top card of the exiled pile into its owner's hand.

Glass Casket

When Glass Casket enters, exile target creature an opponent controls with mana value 3 or less until Glass Casket leaves the battlefield.

The Reality Chip

You may look at the top card of your library any time.
As long as The Reality Chip is attached to a creature, you may play lands and cast spells from the top of your library.
Reconfigure {2}{U} ({2}{U}: Attach to target creature you control; or unattach from a creature. Reconfigure only as a sorcery. While attached, this isn't a creature.)

Renegade Map

Renegade Map enters tapped.
{T}, Sacrifice Renegade Map: Search your library for a basic land card, reveal it, put it into your hand, then shuffle.

Azorius Signet

Sensei's Divining Top

{1}: Look at the top three cards of your library, then put them back in any order.
{T}: Draw a card, then put Sensei's Divining Top on top of its owner's library.

Urza's Saga

(As this Saga enters and after your draw step, add a lore counter. Sacrifice after III.)
I — Urza's Saga gains "{T}: Add {C}."
II — Urza's Saga gains "{2}, {T}: Create a 0/0 colorless Construct artifact creature token with 'This creature gets +1/+1 for each artifact you control.'"
III — Search your library for an artifact card with mana cost {0} or {1}, put it onto the battlefield, then shuffle.

Commander's Sphere

{T}: Add one mana of any color in your commander's color identity.
Sacrifice Commander's Sphere: Draw a card.

Command Tower

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

Scroll Rack

{1}, {T}: Exile any number of cards from your hand face down. Put that many cards from the top of your library into your hand. Then look at the exiled cards and put them on top of your library in any order.

Inspiring Statuary

Nonartifact spells you cast have improvise. (Your artifacts can help cast those spells. Each artifact you tap after you're done activating mana abilities pays for {1}.)

Razortide Bridge

Razortide Bridge enters tapped.
Indestructible
{T}: Add {W} or {U}.

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.

Thought Monitor

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

Voyager Staff

{2}, Sacrifice Voyager Staff: Exile target creature. Return the exiled card to the battlefield under its owner's control at the beginning of the next end step.

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 Kappa Cannoneer or another artifact you control enters, put a +1/+1 counter on Kappa Cannoneer and it can't be blocked this turn.

Arcane Signet

Treasure Vault

{T}: Add {C}.
{X}{X}, {T}, Sacrifice Treasure Vault: Create X Treasure tokens.

Crystal Grotto

When Crystal Grotto enters, scry 1.
{T}: Add {C}.
{1}, {T}: Add one mana of any color.

Foundry Inspector

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

Selesnya Signet

Treasure Cove

(Transforms from Treasure Map.)
{T}: Add {C}.
{T}, Sacrifice a Treasure: Draw a card.

Treasure Map

{1}, {T}: Scry 1. Put a landmark counter on Treasure Map. Then if there are three or more landmark counters on it, remove those counters, transform Treasure Map, and create three Treasure tokens. (They're artifacts with "{T}, Sacrifice this artifact: Add one mana of any color.")

Treasure Map // Treasure Cove

Replicating Ring

{T}: Add one mana of any color.
At the beginning of your upkeep, put a night counter on Replicating Ring. Then if it has eight or more night counters on it, remove all of them and create eight colorless snow artifact tokens named Replicated Ring with "{T}: Add one mana of any color."

Tanglepool Bridge

Tanglepool Bridge enters tapped.
Indestructible
{T}: Add {G} or {U}.

Crystal Shard

{3}, {T} or {U}, {T}: Return target creature to its owner's hand unless its controller pays {1}.

Jhoira's Toolbox

{2}: Regenerate target artifact creature.

Stenn, Paranoid Partisan

As Stenn, Paranoid Partisan enters, choose a card type other than creature or land.
Spells you cast of the chosen type cost {1} less to cast.
{1}{W}{U}: Exile Stenn. Return it to the battlefield under its owner's control at the beginning of the next end step.

Sol Ring

Mirrorworks

Whenever another nontoken artifact you control enters, you may pay {2}. If you do, create a token that's a copy of that artifact.

Hammer of Nazahn

Whenever Hammer of Nazahn or another Equipment you control enters, you may attach that Equipment to target creature you control.
Equipped creature gets +2/+0 and has indestructible.
Equip {4}

Etherium Sculptor

Jade Orb of Dragonkind

{T}: Add {G}. When you spend this mana to cast a Dragon creature spell, it enters with an additional +1/+1 counter on it and gains hexproof until your next turn. (It can't be the target of spells or abilities your opponents control.)

Astral Cornucopia

Astral Cornucopia enters with X charge counters on it.
{T}: Choose a color. Add one mana of that color for each charge counter on Astral Cornucopia.

Dragon's Hoard

Whenever a Dragon you control enters, put a gold counter on Dragon's Hoard.
{T}, Remove a gold counter from Dragon's Hoard: Draw a card.
{T}: Add one mana of any color.

Pearl Medallion

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

Solemn Simulacrum

When this creature enters, you may search your library for a basic land card, put that card onto the battlefield tapped, then shuffle.
When this creature dies, you may draw a card.

Planar Atlas

Planar Atlas enters tapped.
When Planar Atlas enters, you may look at the top four cards of your library. If you do, reveal up to one land card from among them, then put that card on top of your library and the rest on the bottom in a random order.
{T}: Add {C}.

Guild Globe

When Guild Globe enters, draw a card.
{2}, {T}, Sacrifice Guild Globe: Add two mana of different colors.

Lightning Greaves

Equipped creature has haste and shroud. (It can't be the target of spells or abilities.)
Equip {0}

Bronze Walrus

When Bronze Walrus enters, 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.)
{T}: Add one mana of any color.

Burnished Hart

{3}, Sacrifice this creature: Search your library for up to two basic land cards, put them onto the battlefield tapped, then shuffle.

Prototype Portal

Imprint — When Prototype Portal enters, you may exile an artifact card from your hand.
{X}, {T}: Create a token that's a copy of the exiled card. X is the mana value of that card.

Thornglint Bridge

Thornglint Bridge enters tapped.
Indestructible
{T}: Add {G} or {W}.

Fieldmist Borderpost

You may pay {1} and return a basic land you control to its owner's hand rather than pay this spell's mana cost.
Fieldmist Borderpost enters tapped.
{T}: Add {W} or {U}.

Power Depot

Power Depot enters tapped.
{T}: Add {C}.
{T}: Add one mana of any color. Spend this mana only to cast artifact spells or activate abilities of artifacts.
Modular 1

Portable Hole

When Portable Hole enters, exile target nonland permanent an opponent controls with mana value 2 or less until Portable Hole leaves the battlefield.

Ancient Den

Seat of the Synod

Mana Geode

When Mana Geode enters, scry 1.
{T}: Add one mana of any color.

Skyclave Relic

Kicker {3}
Indestructible
When Skyclave Relic enters, if it was kicked, create two tapped tokens that are copies of Skyclave Relic.
{T}: Add one mana of any color.

Corridor Monitor

When Corridor Monitor enters, untap target artifact or creature you control.

Meteor Golem

When this creature enters, destroy target nonland permanent an opponent controls.

Academy Ruins

{T}: Add {C}.
{1}{U}, {T}: Put target artifact card from your graveyard on top of your library.

Chromatic Orrery

You may spend mana as though it were mana of any color.
{T}: Add {C}{C}{C}{C}{C}.
{5}, {T}: Draw a card for each color among permanents you control.

Crystalline Giant

At the beginning of combat on your turn, choose a kind of counter at random that Crystalline Giant doesn't have on it from among flying, first strike, deathtouch, hexproof, lifelink, menace, reach, trample, vigilance, and +1/+1. Put a counter of that kind on Crystalline Giant.

Chromatic Lantern

Lands you control have "{T}: Add one mana of any color."
{T}: Add one mana of any color.

Sisay's Ring

Firemind Vessel

Firemind Vessel enters tapped.
{T}: Add two mana of different colors.

Khalni Gem

When Khalni Gem enters, return two lands you control to their owner's hand.
{T}: Add two mana of any one color.

Simic Signet

Noble's Purse

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

Tree of Tales

Paradise Mantle

Equipped creature has "{T}: Add one mana of any color."
Equip {1}

Wildfield Borderpost

You may pay {1} and return a basic land you control to its owner's hand rather than pay this spell's mana cost.
Wildfield Borderpost enters tapped.
{T}: Add {G} or {W}.

Stonespeaker Crystal

{T}: Add {C}{C}.
{2}, {T}, Sacrifice Stonespeaker Crystal: Exile any number of target players' graveyards. Draw a card.

Scroll of the Masters

Whenever you cast a noncreature spell, put a lore counter on Scroll of the Masters.
{3}, {T}: Target creature you control gets +1/+1 until end of turn for each lore counter on Scroll of the Masters.

Worn Powerstone

Worn Powerstone enters tapped.
{T}: Add {C}{C}.

Automatic Librarian

When Automatic Librarian enters, 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.)

Darksteel Citadel

Scroll of Fate

{T}: Manifest a card from your hand. (Put that card onto the battlefield face down as a 2/2 creature. Turn it face up any time for its mana cost if it's a creature card.)

Silver Raven

Flying
When Silver Raven enters, scry 1. (Look at the top card of your library. You may put that card on the bottom.)