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.

Sol Ring

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.)

Urza's Mine

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

Contagion Engine

When Contagion Engine enters, put a -1/-1 counter on each creature target player controls.
{4}, {T}: Proliferate twice. (Choose any number of permanents and/or players, then give each another counter of each kind already there. Then do it again.)

Sequestered Stash

{T}: Add {C}.
{4}, {T}, Sacrifice Sequestered Stash: Mill five cards. Then you may put an artifact card from your graveyard on top of your library.

Temple of the False God

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

Lux Cannon

{T}: Put a charge counter on Lux Cannon.
{T}, Remove three charge counters from Lux Cannon: Destroy target permanent.

Thran Dynamo

Doubling Cube

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

Shrine of the Forsaken Gods

{T}: Add {C}.
{T}: Add {C}{C}. Spend this mana only to cast colorless spells. Activate only if you control seven or more lands.

Chimeric Mass

Chimeric Mass enters with X charge counters on it.
{1}: Until end of turn, Chimeric Mass becomes a Construct artifact creature with "This creature's power and toughness are each equal to the number of charge counters on it."

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.

Urza's Tower

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

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}.

Unwinding Clock

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

Thought Vessel

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

Trigon of Mending

Trigon of Mending enters with three charge counters on it.
{W}{W}, {T}: Put a charge counter on Trigon of Mending.
{2}, {T}, Remove a charge counter from Trigon of Mending: Target player gains 3 life.

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

Coretapper

{T}: Put a charge counter on target artifact.
Sacrifice Coretapper: Put two charge counters on target artifact.

Everflowing Chalice

Multikicker {2} (You may pay an additional {2} any number of times as you cast this spell.)
Everflowing Chalice enters with a charge counter on it for each time it was kicked.
{T}: Add {C} for each charge counter on Everflowing Chalice.