Urza's Factory

{T}: Add {C}.
{7}, {T}: Create a 2/2 colorless Assembly-Worker artifact creature token.

Scorched Ruins

If this land would enter, sacrifice two untapped lands instead. If you do, put this land onto the battlefield. If you don't, put it into its owner's graveyard.
{T}: Add {C}{C}{C}{C}.

Paradox Engine

Whenever you cast a spell, untap all nonland permanents you control.

Campfire

{1}, {T}: You gain 2 life.
{2}, {T}, Exile this artifact: Put all commanders you own from the command zone and from your graveyard into your hand. Then shuffle your graveyard into your library.

Urza's Workshop

{T}: Add {C}.
Metalcraft — {T}: Add {C} for each Urza's land you control. Activate only if you control three or more artifacts.

Command Beacon

{T}: Add {C}.
{T}, Sacrifice this land: Put your commander into your hand from the command zone.

Liquimetal Torque

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

Walking Atlas

{T}: You may put a land card from your hand onto the battlefield.

Ruins of Oran-Rief

This land enters tapped.
{T}: Add {C}. ({C} represents colorless mana.)
{T}: Put a +1/+1 counter on target colorless creature that entered this turn.

Arc Spitter

Equipped creature has "{1}: This creature deals 1 damage to target creature that's blocking it."
Equip {1} ({1}: Attach to target creature you control. Equip only as a sorcery.)

Forsaken Monument

Colorless creatures you control get +2/+2.
Whenever you tap a permanent for {C}, add an additional {C}.
Whenever you cast a colorless spell, you gain 2 life.

Mystic Forge

You may look at the top card of your library any time.
You may cast artifact spells and colorless spells from the top of your library.
{T}, Pay 1 life: Exile the top card of your library.

Ancient Tomb

{T}: Add {C}{C}. This land deals 2 damage to you.

Wondrous Crucible

Permanents you control have ward {2}.
At the beginning of your end step, mill two cards, then exile a nonland card at random from your graveyard. Copy it. You may cast the copy without paying its mana cost. (A copy of a permanent spell becomes a token.)

Commander's Plate

Equipped creature gets +3/+3 and has protection from each color that's not in your commander's color identity.
Equip commander {3}
Equip {5}

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.

Bonders' Enclave

{T}: Add {C}.
{3}, {T}: Draw a card. Activate only if you control a creature with power 4 or greater.

Karn's Bastion

{T}: Add {C}.
{4}, {T}: Proliferate. (Choose any number of permanents and/or players, then give each another counter of each kind already there.)

Blast Zone

This land enters with a charge counter on it.
{T}: Add {C}.
{X}{X}, {T}: Put X charge counters on this land.
{3}, {T}, Sacrifice this land: Destroy each nonland permanent with mana value equal to the number of charge counters on this land.

Lithoform Engine

{2}, {T}: Copy target activated or triggered ability you control. You may choose new targets for the copy.
{3}, {T}: Copy target instant or sorcery spell you control. You may choose new targets for the copy.
{4}, {T}: Copy target permanent spell you control. (The copy becomes a token.)

All Is Dust

Each player sacrifices all permanents they control that are one or more colors.

Mishra's Workshop

{T}: Add {C}{C}{C}. Spend this mana only to cast artifact spells.

Ugin, the Ineffable

Colorless spells you cast cost {2} less to cast.
+1: Exile the top card of your library face down and look at it. Create a 2/2 colorless Spirit creature token. When that token leaves the battlefield, put the exiled card into your hand.
−3: Destroy target permanent that's one or more colors.

Candy Trail

When this artifact enters, scry 2.
{2}, {T}, Sacrifice this artifact: You gain 3 life and draw a card.

Karn, Silver Golem

Whenever Karn blocks or becomes blocked, it gets -4/+4 until end of turn.
{1}: Target noncreature artifact becomes an artifact creature with power and toughness each equal to its mana value until end of turn.

Aetherflux Reservoir

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

Guildless Commons

This land enters tapped.
When this land enters, return a land you control to its owner's hand.
{T}: Add {C}{C}.

Arcane Lighthouse

{T}: Add {C}.
{1}, {T}: Until end of turn, creatures your opponents control lose hexproof and shroud and can't have hexproof or shroud.

The One Ring

Indestructible
When The One Ring enters, if you cast it, you gain protection from everything until your next turn.
At the beginning of your upkeep, you lose 1 life for each burden counter on The One Ring.
{T}: Put a burden counter on The One Ring, then draw a card for each burden counter on The One Ring.

Helm of the Host

At the beginning of combat on your turn, create a token that's a copy of equipped creature, except the token isn't legendary. That token gains haste.
Equip {5}

Tomb of the Spirit Dragon

{T}: Add {C}.
{2}, {T}: You gain 1 life for each colorless creature you control.

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 this artifact on top of its owner's library.

Darksteel Citadel

Urza's Tower

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

Liquimetal Coating

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

Helm of Awakening

Vedalken Orrery

You may cast spells as though they had flash.

Candelabra of Tawnos

Temple of the False God

{T}: Add {C}{C}. Activate only if you control five or more lands.

Deserted Temple

{T}: Add {C}.
{1}, {T}: Untap target land.

Metalworker

{T}: Reveal any number of artifact cards in your hand. Add {C}{C} for each card revealed this way.

Luxior, Giada's Gift

Equipped creature gets +1/+1 for each counter on it.
Equipped permanent isn't a planeswalker and is a creature in addition to its other types. (Loyalty abilities can still be activated.)
Equip planeswalker {1}
Equip {3}

Urza's Mine

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

Manakin

Bronze Cudgels

{2}: Until end of turn, equipped creature gets +X/+0, where X is the number of times this ability has resolved this turn.
Equip {1} ({1}: Attach to target creature you control. Equip only as a sorcery.)

City of Traitors

When you play another land, sacrifice this land.
{T}: Add {C}{C}.

Platinum Emperion

Your life total can't change. (You can't gain or lose life. You can't pay any amount of life except 0.)

Doubling Cube

{3}, {T}: Double the amount of each type of unspent mana you have.

Wastes

Fractured Powerstone

{T}: Add {C}.
{T}: Roll the planar die. Activate only as a sorcery.

Urza's Power Plant

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

Detection Tower

{T}: Add {C}.
{1}, {T}: Until end of turn, your opponents and creatures your opponents control with hexproof can be the targets of spells and abilities you control as though they didn't have hexproof.

Basalt Monolith

This artifact doesn't untap during your untap step.
{T}: Add {C}{C}{C}.
{3}: Untap this artifact.

Ashnod's Transmogrant

{T}, Sacrifice this artifact: Put a +1/+1 counter on target nonartifact creature. That creature becomes an artifact in addition to its other types.

Forcefield

{1}: The next time an unblocked creature of your choice would deal combat damage to you this turn, prevent all but 1 of that damage.

Crystal Vein

{T}: Add {C}.
{T}, Sacrifice this land: Add {C}{C}.

Horizon Stone

If you would lose unspent mana, that mana becomes colorless instead.

Hedron Crawler

{T}: Add {C}. ({C} represents colorless mana.)

War Room

{T}: Add {C}.
{3}, {T}, Pay life equal to the number of colors in your commanders' color identity: Draw a card.