Razortide Bridge

Razortide Bridge enters tapped.
Indestructible
{T}: Add {W} or {U}.

Frogmite

Affinity for artifacts (This spell costs {1} less to cast for each artifact you control.)

Gingerbrute

Haste (This creature can attack and {T} as soon as it comes under your control.)
{1}: Gingerbrute can't be blocked this turn except by creatures with haste.
{2}, {T}, Sacrifice Gingerbrute: You gain 3 life.

Thraben Inspector

When Thraben Inspector enters, investigate. (Create a Clue token. It's an artifact with "{2}, Sacrifice this artifact: Draw a card.")

Reverse Engineer

Improvise (Your artifacts can help cast this spell. Each artifact you tap after you're done activating mana abilities pays for {1}.)
Draw three cards.

Plains

Springleaf Drum

{T}, Tap an untapped creature you control: Add one mana of any color.

Ancient Den

Thoughtcast

Affinity for artifacts (This spell costs {1} less to cast for each artifact you control.)
Draw two cards.

Vault Skirge

({B/P} can be paid with either {B} or 2 life.)
Flying
Lifelink (Damage dealt by this creature also causes you to gain that much life.)

Island

Seat of the Synod

Ornithopter

Darksteel Citadel

All That Glitters

Enchant creature
Enchanted creature gets +1/+1 for each artifact and/or enchantment you control.

Chromatic Star

{1}, {T}, Sacrifice Chromatic Star: Add one mana of any color.
When Chromatic Star is put into a graveyard from the battlefield, draw a card.

Metallic Rebuke

Improvise (Your artifacts can help cast this spell. Each artifact you tap after you're done activating mana abilities pays for {1}.)
Counter target spell unless its controller pays {3}.