Zhalfirin Void

When Zhalfirin Void enters the battlefield, scry 1. (Look at the top card of your library. You may put that card on the bottom of your library.)
{T}: Add {C}.

Phyrexia's Core

{T}: Add {C}.
{1}, {T}, Sacrifice an artifact: You gain 1 life.

Arch of Orazca

Ascend (If you control ten or more permanents, you get the city's blessing for the rest of the game.)
{T}: Add {C}.
{5}, {T}: Draw a card. Activate only if you have the city's blessing.

Urza's Tower

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

Tectonic Edge

{T}: Add {C}.
{1}, {T}, Sacrifice Tectonic Edge: Destroy target nonbasic land. Activate only if an opponent controls four or more lands.

Crystal Vein

{T}: Add {C}.
{T}, Sacrifice Crystal Vein: Add {C}{C}.

Field of Ruin

{T}: Add {C}.
{2}, {T}, Sacrifice Field of Ruin: Destroy target nonbasic land an opponent controls. Each player searches their library for a basic land card, puts it onto the battlefield, then shuffles.

Ghost Quarter

{T}: Add {C}.
{T}, Sacrifice Ghost Quarter: Destroy target land. Its controller may search their library for a basic land card, put it onto the battlefield, then shuffle.

Reliquary Tower

You have no maximum hand size.
{T}: Add {C}.

Ulalek, Fused Atrocity

Devoid (This card has no color.)
Whenever you cast an Eldrazi spell, you may pay {C}{C}. If you do, copy all spells you control, then copy all other activated and triggered abilities you control. You may choose new targets for the copies. (Mana abilities can't be copied.)

Blinkmoth Well

{T}: Add {C}.
{2}, {T}: Tap target noncreature artifact.

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.

Buried Ruin

{T}: Add {C}.
{2}, {T}, Sacrifice Buried Ruin: Return target artifact card from your graveyard to your hand.

Nephalia Academy

If a spell or ability an opponent controls causes you to discard a card, you may reveal that card and put it on top of your library instead of putting it anywhere else.
{T}: Add {C}.

Inventors' Fair

At the beginning of your upkeep, if you control three or more artifacts, you gain 1 life.
{T}: Add {C}.
{4}, {T}, Sacrifice Inventors' Fair: Search your library for an artifact card, reveal it, put it into your hand, then shuffle. Activate only if you control three or more artifacts.

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.

Encroaching Wastes

{T}: Add {C}.
{4}, {T}, Sacrifice Encroaching Wastes: Destroy target nonbasic land.

Mystifying Maze

{T}: Add {C}.
{4}, {T}: Exile target attacking creature an opponent controls. At the beginning of the next end step, return it to the battlefield tapped under its owner's control.

Throne of the High City

{T}: Add {C}.
{4}, {T}, Sacrifice Throne of the High City: You become the monarch.

Mage-Ring Network

{T}: Add {C}.
{1}, {T}: Put a storage counter on Mage-Ring Network.
{T}, Remove any number of storage counters from Mage-Ring Network: Add {C} for each storage counter removed this way.

Wastes

Guildless Commons

Guildless Commons enters the battlefield tapped.
When Guildless Commons enters the battlefield, return a land you control to its owner's hand.
{T}: Add {C}{C}.

Urza's Power Plant

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

Darksteel Citadel

Urza's Factory

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

Treasure Vault

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

Urza's Mine

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