Orzhov Signet

Thopter Foundry

{1}, Sacrifice a nontoken artifact: Create a 1/1 blue Thopter artifact creature token with flying. You gain 1 life.

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.

Goldmire Bridge

This land enters tapped.
Indestructible
{T}: Add {W} or {B}.

Darkwater Catacombs

Bjorna, Nightfall Alchemist

{T}, Sacrifice an artifact: Bjorna, Nightfall Alchemist deals 1 damage to target creature. Goad that creature. (Until your next turn, that creature attacks each combat if able and attacks a player other than you if able.)
Partner—Friends forever (You can have two commanders if both have this ability.)

Izzet Signet

Razortide Bridge

This land enters tapped.
Indestructible
{T}: Add {W} or {U}.

Silverbluff Bridge

This land enters tapped.
Indestructible
{T}: Add {U} or {R}.

Seat of the Synod

Azorius Signet

Etherium Sculptor

Artifact spells you cast cost {1} less to cast.

Breya, Etherium Shaper

When Breya enters, create two 1/1 blue Thopter artifact creature tokens with flying.
{2}, Sacrifice two artifacts: Choose one —
• Breya deals 3 damage to target player or planeswalker.
• Target creature gets -4/-4 until end of turn.
• You gain 5 life.

Sharuum the Hegemon

Flying
When Sharuum enters, you may return target artifact card from your graveyard to the battlefield.

Shadowblood Ridge

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.)

Enthusiastic Mechanaut

Flying
Artifact spells you cast cost {1} less to cast.

Exotic Orchard

{T}: Add one mana of any color that a land an opponent controls could produce.

Agent of the Iron Throne

Commander creatures you own have "Whenever an artifact or creature you control is put into a graveyard from the battlefield, each opponent loses 1 life."

Vault of Whispers

Wernog, Rider's Chaplain

When Wernog, Rider's Chaplain enters or leaves the battlefield, each opponent may investigate. Each opponent who doesn't loses 1 life. You investigate X times, where X is one plus the number of opponents who investigated this way.
Partner—Friends forever (You can have two commanders if both have this ability.)

Drossforge Bridge

This land enters tapped.
Indestructible
{T}: Add {B} or {R}.

Mistvault Bridge

This land enters tapped.
Indestructible
{T}: Add {U} or {B}.

Skycloud Expanse

Sword of the Meek

Equipped creature gets +1/+2.
Equip {2}
Whenever a 1/1 creature you control enters, you may return this card from your graveyard to the battlefield, then attach it to that creature.

Caves of Koilos

{T}: Add {C}.
{T}: Add {W} or {B}. This land deals 1 damage to you.

Sphinx Summoner

Flying
When this creature enters, you may search your library for an artifact creature card, reveal it, put it into your hand. then shuffle.