Have

Clockwork Beetle

Clockwork Beetle enters with two +1/+1 counters on it.
Whenever Clockwork Beetle attacks or blocks, remove a +1/+1 counter from it at end of combat.

Counterspell

Mask of the Mimic

As an additional cost to cast this spell, sacrifice a creature.
Search your library for a card with the same name as target nontoken creature, put that card onto the battlefield, then shuffle.

Moonsilver Key

{1}, {T}, Sacrifice Moonsilver Key: Search your library for an artifact card with a mana ability or a basic land card, reveal it, put it into your hand, then shuffle.

Glimmervoid

At the beginning of the end step, if you control no artifacts, sacrifice Glimmervoid.
{T}: Add one mana of any color.

Eviscerator's Insight

As an additional cost to cast this spell, sacrifice an artifact or creature.
Draw two cards.
Flashback {4}{B} (You may cast this card from your graveyard for its flashback cost and any additional costs. Then exile it.)

Tolarian Academy

{T}: Add {U} for each artifact you control.

Ingenious Smith

When Ingenious Smith enters, look at the top four cards of your library. You may reveal an artifact card from among them and put it into your hand. Put the rest on the bottom of your library in a random order.
Whenever one or more artifacts you control enter, put a +1/+1 counter on Ingenious Smith. This ability triggers only once each turn.

Mechtitan Core

{5}, Exile Mechtitan Core and four other artifact creatures and/or Vehicles you control: Create Mechtitan, a legendary 10/10 Construct artifact creature token with flying, vigilance, trample, lifelink, and haste that's all colors. When that token leaves the battlefield, return all cards exiled with Mechtitan Core except Mechtitan Core to the battlefield tapped under their owners' control.
Crew 2

Island

Goldmire Bridge

Goldmire Bridge enters tapped.
Indestructible
{T}: Add {W} or {B}.

Skeleton Shard

{3}, {T} or {B}, {T}: Return target artifact creature card from your graveyard to your hand.

Mistvault Bridge

Mistvault Bridge enters tapped.
Indestructible
{T}: Add {U} or {B}.

Enlightened Tutor

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

Plains

Swamp

Helm of the Host

At the beginning of combat on your turn, create a token that's a copy of equipped creature, except the token isn't legendary. That token gains haste.
Equip {5}

Demonic Tutor

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

Fabricate

Search your library for an artifact card, reveal it, put it into your hand, then shuffle.

Sword of Light and Shadow

Equipped creature gets +2/+2 and has protection from white and from black.
Whenever equipped creature deals combat damage to a player, you gain 3 life and you may return up to one target creature card from your graveyard to your hand.
Equip {2}

Whispersilk Cloak

Equipped creature can't be blocked and has shroud. (It can't be the target of spells or abilities.)
Equip {2}

The Ozolith

Whenever a creature you control leaves the battlefield, if it had counters on it, put those counters on The Ozolith.
At the beginning of combat on your turn, if The Ozolith has counters on it, you may move all counters from The Ozolith onto target creature.

Dress Down

Flash
When Dress Down enters, draw a card.
Creatures lose all abilities.
At the beginning of the end step, sacrifice Dress Down.