Darksteel Citadel

Ichor Wellspring

When Ichor Wellspring enters or is put into a graveyard from the battlefield, draw a card.

Metalwork Colossus

This spell costs {X} less to cast, where X is the total mana value of noncreature artifacts you control.
Sacrifice two artifacts: Return Metalwork Colossus from your graveyard to your hand.

Jwar Isle Refuge

Jwar Isle Refuge enters tapped.
When Jwar Isle Refuge enters, you gain 1 life.
{T}: Add {U} or {B}.

Rogue's Passage

{T}: Add {C}.
{4}, {T}: Target creature can't be blocked this turn.

Metalspinner's Puzzleknot

When Metalspinner's Puzzleknot enters, you draw a card and you lose 1 life.
{2}{B}, Sacrifice Metalspinner's Puzzleknot: You draw a card and you lose 1 life.

Dimir Keyrune

{T}: Add {U} or {B}.
{U}{B}: Dimir Keyrune becomes a 2/2 blue and black Horror artifact creature until end of turn and can't be blocked this turn.

Defense Grid

Each spell costs {3} more to cast except during its controller's turn.

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.

Skilled Animator

When Skilled Animator enters, target artifact you control becomes an artifact creature with base power and toughness 5/5 for as long as Skilled Animator remains on the battlefield.

Battle at the Bridge

Improvise (Your artifacts can help cast this spell. Each artifact you tap after you're done activating mana abilities pays for {1}.)
Target creature gets -X/-X until end of turn. You gain X life.

Island

Tezzeret, Master of Metal

+1: Reveal cards from the top of your library until you reveal an artifact card. Put that card into your hand and the rest on the bottom of your library in a random order.
−3: Target opponent loses life equal to the number of artifacts you control.
−8: Gain control of all artifacts and creatures target opponent controls.

Swamp

Ensoul Artifact

Enchant artifact
Enchanted artifact is a creature with base power and toughness 5/5 in addition to its other types.

Tezzeret's Betrayal

Destroy target creature. You may search your library and/or graveyard for a card named Tezzeret, Master of Metal, reveal it, and put it into your hand. If you search your library this way, shuffle.

Tezzeret's Touch

Enchant artifact
Enchanted artifact is a creature with base power and toughness 5/5 in addition to its other types.
When enchanted artifact is put into a graveyard, return that card to its owner's hand.

Bloodletter Quill

{2}, {T}, Put a blood counter on Bloodletter Quill: Draw a card, then you lose 1 life for each blood counter on Bloodletter Quill.
{U}{B}: Remove a blood counter from Bloodletter Quill.