Hargilde, Kindly Runechanter

{T}: Add {C}{C}. Spend this mana only to cast artifact spells or activate abilities of artifacts.
Friends forever (You can have two commanders if both have friends forever.)

Vedalken Archmage

Whenever you cast an artifact spell, draw a card.

Jhoira's Familiar

Flying
Historic spells you cast cost {1} less to cast. (Artifacts, legendaries, and Sagas are historic.)

Malcolm, the Eyes

Flying, haste
Whenever you cast your second spell each turn, investigate. (Create a Clue token. It's an artifact with "{2}, Sacrifice this artifact: Draw a card.")

Scrap Trawler

Whenever Scrap Trawler or another artifact you control is put into a graveyard from the battlefield, return to your hand target artifact card in your graveyard with lesser mana value.

Izzet Cluestone

{T}: Add {U} or {R}.
{U}{R}, {T}, Sacrifice Izzet Cluestone: Draw a card.

Seat of the Synod

Time Sieve

{T}, Sacrifice five artifacts: Take an extra turn after this one.

Steel Overseer

{T}: Put a +1/+1 counter on each artifact creature you control.

Lavinia, Foil to Conspiracy

Vigilance
Whenever you cast your second spell each turn, investigate. (Create a Clue token. It's an artifact with "{2}, Sacrifice this artifact: Draw a card.")
{T}: Add {C}{C}. Activate only during an opponent's turn.

Gleaming Geardrake

Flying
When Gleaming Geardrake enters, investigate. (Create a Clue token. It's an artifact with "{2}, Sacrifice this artifact: Draw a card.")
Whenever you sacrifice an artifact, put a +1/+1 counter on Gleaming Geardrake.

Palladium Myr

Curious Inquiry

Enchant creature
Enchanted creature gets +1/+1 and has "Whenever this creature deals combat damage to a player, investigate." (Create a Clue token. It's an artifact with "{2}, Sacrifice this artifact: Draw a card.")

Library

Library enters tapped.
{T}: Add {U} or {R}.
{4}, {T}: Investigate. (Create a Clue token. It's an artifact with "{2}, Sacrifice this artifact: Draw a card.")

Study

Study enters tapped.
{T}: Add {W} or {U}.
{4}, {T}: Investigate. (Create a Clue token. It's an artifact with "{2}, Sacrifice this artifact: Draw a card.")

Pearl Medallion

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

Resonance Technician

Flying
When Resonance Technician enters, you may discard a card. If you do, investigate twice.
{T}, Tap X untapped artifacts you control: Copy target instant or sorcery spell you control with mana value X. You may choose new targets for the copy.

Academy Manufactor

If you would create a Clue, Food, or Treasure token, instead create one of each.

Follow Him

Investigate X times. (Then exile this card. You may cast the creature later from exile.)

James, Wandering Dad

{T}: Add {C}{C}. Spend this mana only to activate abilities.

James, Wandering Dad // Follow Him

Tamiyo's Journal

At the beginning of your upkeep, investigate. (Create a Clue token. It's an artifact with "{2}, Sacrifice this artifact: Draw a card.")
{T}, Sacrifice three Clues: Search your library for a card, put that card into your hand, then shuffle.

Ezrim, Agency Chief

Flying
When Ezrim, Agency Chief enters, investigate twice. (To investigate, create a Clue token. It's an artifact with "{2}, Sacrifice this artifact: Draw a card.")
{1}, Sacrifice an artifact: Ezrim gains your choice of vigilance, lifelink, or hexproof until end of turn.

Confirm Suspicions

Counter target spell.
Investigate three times. (To investigate, create a Clue token. It's an artifact with "{2}, Sacrifice this artifact: Draw a card.")

Enthusiastic Mechanaut

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

Detective's Satchel

When Detective's Satchel enters, investigate twice. (To investigate, create a Clue token. It's an artifact with "{2}, Sacrifice this artifact: Draw a card.")
{T}: Create a 1/1 colorless Thopter artifact creature token with flying. Activate only if you've sacrificed an artifact this turn.

Zirda, the Dawnwaker

Companion — Each permanent card in your starting deck has an activated ability. (If this card is your chosen companion, you may put it into your hand from outside the game for {3} as a sorcery.)
Abilities you activate that aren't mana abilities cost {2} less to activate. This effect can't reduce the mana in that cost to less than one mana.
{1}, {T}: Target creature can't block this turn.

Hall

Hall enters tapped.
{T}: Add {R} or {W}.
{4}, {T}: Investigate. (Create a Clue token. It's an artifact with "{2}, Sacrifice this artifact: Draw a card.")

Foundry Inspector

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

Hanna, Ship's Navigator

{1}{W}{U}, {T}: Return target artifact or enchantment card from your graveyard to your hand.

Meddling Youths

Haste
Whenever you attack with three or more creatures, investigate. (Create a Clue token. It's an artifact with "{2}, Sacrifice this artifact: Draw a card.")

Forensic Gadgeteer

Whenever you cast an artifact spell, investigate. (Create a Clue token. It's an artifact with "{2}, Sacrifice this artifact: 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.

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.)
Friends forever (You can have two commanders if both have friends forever.)

Alquist Proft, Master Sleuth

Vigilance
When Alquist Proft, Master Sleuth enters, investigate. (Create a Clue token. It's an artifact with "{2}, Sacrifice this artifact: Draw a card.")
{X}{W}{U}{U}, {T}, Sacrifice a Clue: You draw X cards and gain X life.

Etherium Sculptor

Bygone Bishop

Flying
Whenever you cast a creature spell with mana value 3 or less, investigate. (Create a Clue token. It's an artifact with "{2}, Sacrifice this artifact: Draw a card.")

Shimmer Myr

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

Sophina, Spearsage Deserter

Menace
Whenever Sophina, Spearsage Deserter attacks, investigate once for each nontoken attacking creature. (To investigate, create a Clue token. It's an artifact with "{2}, Sacrifice this artifact: Draw a card.")
Friends forever (You can have two commanders if both have friends forever.)

Piper Wright, Publick Reporter

Whenever Piper Wright deals combat damage to a player, investigate that many times. (To investigate, create a Clue token. It's an artifact with "{2}, Sacrifice this artifact: Draw a card.")
Whenever you sacrifice a Clue, put a +1/+1 counter on target creature you control.

Senator Peacock

Artifacts you control are Clues in addition to their other types and have "{2}, Sacrifice this artifact: Draw a card."
Whenever you sacrifice a Clue, target creature can't be blocked this turn.

Ancient Den

Great Furnace

Deduce

Draw a card. Investigate. (Create a Clue token. It's an artifact with "{2}, Sacrifice this artifact: Draw a card.")