Cogwork Wrestler

Flash
When Cogwork Wrestler enters, target creature an opponent controls gets -2/-0 until end of turn.

Experimental Synthesizer

When Experimental Synthesizer enters or leaves the battlefield, exile the top card of your library. Until end of turn, you may play that card.
{2}{R}, Sacrifice Experimental Synthesizer: Create a 2/2 white Samurai creature token with vigilance. Activate only as a sorcery.

Myr Enforcer

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

Journey to Nowhere

When Journey to Nowhere enters, exile target creature.
When Journey to Nowhere leaves the battlefield, return the exiled card to the battlefield under its owner's control.

Springleaf Drum

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

Ephemerate

Exile target creature you control, then return it to the battlefield under its owner's control.
Rebound (If you cast this spell from your hand, exile it as it resolves. At the beginning of your next upkeep, you may cast this card from exile without paying its mana cost.)

Thraben Charm

Choose one —
• Thraben Charm deals damage equal to twice the number of creatures you control to target creature.
• Destroy target enchantment.
• Exile any number of target players' graveyards.

Silverbluff Bridge

Silverbluff Bridge enters tapped.
Indestructible
{T}: Add {U} or {R}.

Brainstorm

Draw three cards, then put two cards from your hand on top of your library in any order.

Mightstone's Animation

Enchant artifact
When Mightstone's Animation enters, draw a card.
Enchanted artifact is a creature with base power and toughness 4/4 in addition to its other types.

Thraben Inspector

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

Darksteel Citadel

Galvanic Blast

Galvanic Blast deals 2 damage to any target.
Metalcraft — Galvanic Blast deals 4 damage instead if you control three or more artifacts.

Recommission

Return target artifact or creature card with mana value 3 or less from your graveyard to the battlefield. If a creature enters this way, it enters with an additional +1/+1 counter on it.

Gearseeker Serpent

This spell costs {1} less to cast for each artifact you control.
{5}{U}: Gearseeker Serpent can't be blocked this turn.

Hydroblast

Choose one —
• Counter target spell if it's red.
• Destroy target permanent if it's red.

Tinker's Tote

When Tinker's Tote enters, create two 1/1 colorless Gnome artifact creature tokens.
{W}, Sacrifice Tinker's Tote: You gain 3 life.

Krark-Clan Shaman

Sacrifice an artifact: Krark-Clan Shaman deals 1 damage to each creature without flying.

Ancient Den

Plains

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.

Thoughtcast

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

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}.

Etherium Spinner

Whenever you cast a spell with mana value 4 or greater, create a 1/1 colorless Thopter artifact creature token with flying.

Spell Pierce

Counter target noncreature spell unless its controller pays {2}.

Glint Hawk

Flying
When Glint Hawk enters, sacrifice it unless you return an artifact you control to its owner's hand.

Ardent Recruit

Metalcraft — Ardent Recruit gets +2/+2 as long as you control three or more artifacts.

Cleansing Wildfire

Destroy target land. Its controller may search their library for a basic land card, put it onto the battlefield tapped, then shuffle.
Draw a card.

Candy Trail

When Candy Trail enters, scry 2.
{2}, {T}, Sacrifice Candy Trail: You gain 3 life and draw a card.

Rustvale Bridge

Rustvale Bridge enters tapped.
Indestructible
{T}: Add {R} or {W}.

Eyes of Gitaxias

Incubate 3. (Create an Incubator token with three +1/+1 counters on it and "{2}: Transform this artifact." It transforms into a 0/0 Phyrexian artifact creature.)
Draw a card.

Seat of the Synod

Ghostly Flicker

Exile two target artifacts, creatures, and/or lands you control, then return those cards to the battlefield under your control.

Razortide Bridge

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

Filigree Attendant

Flying
Filigree Attendant's power is equal to the number of artifacts you control.

Novice Inspector

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

Dispel

Quicksilver Behemoth

Affinity for artifacts (This spell costs {1} less to cast for each artifact you control.)
When Quicksilver Behemoth attacks or blocks, return it to its owner's hand at end of combat. (Return it only if it's on the battlefield.)

Island

Kenku Artificer

Homunculus Servant — When Kenku Artificer enters, put three +1/+1 counters on up to one target noncreature artifact. That artifact becomes a 0/0 Homunculus artifact creature with flying.