Tarrian's Soulcleaver

Equipped creature has vigilance.
Whenever another artifact or creature is put into a graveyard from the battlefield, put a +1/+1 counter on equipped creature.
Equip {2}

Roadside Reliquary

{T}: Add {C}.
{2}, {T}, Sacrifice this land: Draw a card if you control an artifact. Draw a card if you control an enchantment.

Leaden Myr

Clan Crafter

Commander creatures you own have "{2}, Sacrifice an artifact: Put a +1/+1 counter on this creature and draw a card."

Swamp

Thought Monitor

Affinity for artifacts (This spell costs {1} less to cast for each artifact you control.)
Flying
When this creature enters, draw two cards.

Eloise, Nephalia Sleuth

Whenever another creature you control dies, investigate. (Create a Clue token. It's an artifact with "{2}, Sacrifice this token: Draw a card.")
Whenever you sacrifice a token, surveil 1. (Look at the top card of your library. You may put that card into your graveyard.)

Fanatical Offering

As an additional cost to cast this spell, sacrifice an artifact or creature.
Draw two cards and create a Map token. (It's an artifact with "{1}, {T}, Sacrifice this token: Target creature you control explores. Activate only as a sorcery.")

Shield Sphere

Defender
Whenever this creature blocks, put a -0/-1 counter on it.

Memnite

Canoptek Scarab Swarm

Flying
Feeder Mandibles — When this creature enters, exile target player's graveyard. For each artifact or land card exiled this way, create a 1/1 colorless Insect artifact creature token with flying.

Marionette Master

Fabricate 3 (When this creature enters, put three +1/+1 counters on it or create three 1/1 colorless Servo artifact creature tokens.)
Whenever an artifact you control is put into a graveyard from the battlefield, target opponent loses life equal to this creature's power.

Emry, Lurker of the Loch

Affinity for artifacts (This spell costs {1} less to cast for each artifact you control.)
When Emry enters, mill four cards.
{T}: Choose target artifact card in your graveyard. You may cast that card this turn. (You still pay its costs. Timing rules still apply.)

Drown in the Loch

Choose one —
• Counter target spell with mana value less than or equal to the number of cards in its controller's graveyard.
• Destroy target creature with mana value less than or equal to the number of cards in its controller's graveyard.

Eaten Alive

As an additional cost to cast this spell, sacrifice a creature or pay {3}{B}.
Exile target creature or planeswalker.

Shimmer Myr

Flash
You may cast artifact spells as though they had flash.

Executioner's Capsule

{1}{B}, {T}, Sacrifice this artifact: Destroy target nonblack creature.

Ornithopter

Overwhelming Remorse

This spell costs {1} less to cast for each creature card in your graveyard.
Exile target creature or planeswalker.

Ornithopter of Paradise

Phyrexian Walker

Silver Myr

Counterspell

Disciple of the Vault

Whenever an artifact is put into a graveyard from the battlefield, you may have target opponent lose 1 life.

Liberator, Urza's Battlethopter

Flash
Flying
You may cast colorless spells and artifact spells as though they had flash.
Whenever you cast a spell, if the amount of mana spent to cast that spell is greater than Liberator's power, put a +1/+1 counter on Liberator.

Viconia, Drow Apostate

At the beginning of your upkeep, if there are four or more creature cards in your graveyard, return a creature card at random from your graveyard to your hand.
Choose a Background (You can have a Background as a second commander.)

Shardless Outlander

Trample (This creature can deal excess combat damage to the player or planeswalker it's attacking.)
Basic landcycling {2} ({2}, Discard this card: Search your library for a basic land card, reveal it, put it into your hand, then shuffle.)

Island

Baleful Strix

Flying, deathtouch
When this creature enters, draw a card.

Sol Ring

Liquimetal Torque

{T}: Add {C}.
{T}: Target nonland permanent becomes an artifact in addition to its other types until end of turn.

Marionette Apprentice

Fabricate 1 (When this creature enters, put a +1/+1 counter on it or create a 1/1 colorless Servo artifact creature token.)
Whenever another creature or artifact you control is put into a graveyard from the battlefield, each opponent loses 1 life.

Arcane Signet

{T}: Add one mana of any color in your commander's color identity.

Forensic Gadgeteer

Whenever you cast an artifact spell, investigate. (Create a Clue token. It's an artifact with "{2}, Sacrifice this token: Draw a card.")
Activated abilities of artifacts you control cost {1} less to activate. This effect can't reduce the mana in that cost to less than one mana.