Darksteel Citadel

Mycosynth Golem

Affinity for artifacts (This spell costs {1} less to cast for each artifact you control.)
Artifact creature spells you cast have affinity for artifacts. (They cost {1} less to cast for each artifact you control.)

Forest

Pyrite Spellbomb

{R}, Sacrifice this artifact: It deals 2 damage to any target.
{1}, Sacrifice this artifact: Draw a card.

Tree of Tales

Aluren

Any player may cast creature spells with mana value 3 or less without paying their mana costs and as though they had flash.

Junk Diver

Flying
When this creature dies, return another target artifact card from your graveyard to your hand.

Myr Retriever

When this creature dies, return another target artifact card from your graveyard to your hand.

Goblin Welder

{T}: Choose target artifact a player controls and target artifact card in that player's graveyard. If both targets are still legal as this ability resolves, that player simultaneously sacrifices the artifact and returns the artifact card to the battlefield.

Grinding Station

{T}, Sacrifice an artifact: Target player mills three cards.
Whenever an artifact enters, you may untap this artifact.

Great Furnace

Summoner's Egg

Imprint — When this creature enters, you may exile a card from your hand face down.
When this creature dies, turn the exiled card face up. If it's a creature card, put it onto the battlefield under your control.

Gamble

Search your library for a card, put that card into your hand, discard a card at random, then shuffle.

Blasting Station

{T}, Sacrifice a creature: This artifact deals 1 damage to any target.
Whenever a creature enters, you may untap this artifact.