Ancient Den

Unwinding Clock

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

Icy Manipulator

{1}, {T}: Tap target artifact, creature, or land.

Chitterspitter

At the beginning of your upkeep, you may sacrifice a token. If you do, put an acorn counter on Chitterspitter.
Squirrels you control get +1/+1 for each acorn counter on Chitterspitter.
{G}, {T}: Create a 1/1 green Squirrel creature token.

Shimmer Myr

Flash
You may cast artifact spells as though they had flash.

Thornglint Bridge

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

Propaganda

Creatures can't attack you unless their controller pays {2} for each creature they control that's attacking you.

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

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.

Enlightened Tutor

Search your library for an artifact or enchantment card, reveal it, then shuffle and put that card on top.

Meekstone

Creatures with power 3 or greater don't untap during their controllers' untap steps.

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.

Darksteel Citadel

Winter Orb

As long as Winter Orb is untapped, players can't untap more than one land during their untap steps.

Lodestone Golem

Nonartifact spells cost {1} more to cast.

Aura of Silence

Artifact and enchantment spells your opponents cast cost {2} more to cast.
Sacrifice Aura of Silence: Destroy target artifact or enchantment.