Stoic Rebuttal

Metalcraft — This spell costs {1} less to cast if you control three or more artifacts.
Counter target spell.

Great Desert Prospector

When Great Desert Prospector enters, create a tapped Powerstone token for each other creature you control. (They're artifacts with "{T}: Add {C}. This mana can't be spent to cast a nonartifact spell.")

Dispense Justice

Target player sacrifices an attacking creature of their choice.
Metalcraft — That player sacrifices two attacking creatures of their choice instead if you control three or more artifacts.

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.")

Dispatch

Tap target creature.
Metalcraft — If you control three or more artifacts, exile that creature.

Fountain Watch

Artifacts and enchantments you control have shroud. (They can't be the targets of spells or abilities.)

Magnifying Glass

{T}: Add {C}.
{4}, {T}: Investigate. (Create a Clue token. It's an artifact with "{2}, Sacrifice this artifact: Draw a card.")

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.

Reverse Engineer

Improvise (Your artifacts can help cast this spell. Each artifact you tap after you're done activating mana abilities pays for {1}.)
Draw three cards.

Officious Interrogation

This spell costs {W}{U} more to cast for each target beyond the first.
Choose any number of target players. Investigate X times, where X is the total number of creatures those players control.

Mistway Spy

Flying
Disguise {1}{U} (You may cast this card face down for {3} as a 2/2 creature with ward {2}. Turn it face up any time for its disguise cost.)
When Mistway Spy is turned face up, until end of turn, whenever a creature you control deals combat damage to a player, investigate.

Castle Vantress

Castle Vantress enters tapped unless you control an Island.
{T}: Add {U}.
{2}{U}{U}, {T}: Scry 2.

Radiant Fountain

When Radiant Fountain enters, you gain 2 life.
{T}: Add {C}.

Deduce

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

Inspiring Statuary

Nonartifact spells you cast have improvise. (Your artifacts can help cast those spells. Each artifact you tap after you're done activating mana abilities pays for {1}.)

Gates of Istfell

Gates of Istfell enters tapped.
{T}: Add {W}.
{2}{W}{U}{U}, {T}, Sacrifice Gates of Istfell: You gain 2 life and draw two cards.

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.

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.

Cold Case Cracker

Flying
When Cold Case Cracker dies, investigate. (Create a Clue token. It's an artifact with "{2}, Sacrifice this artifact: Draw a card.")

Machinate

Look at the top X cards of your library, where X is the number of artifacts you control. Put one of those cards into your hand and the rest on the bottom of your library in any order.

Citadel Gate

Citadel Gate enters tapped.
As Citadel Gate enters, choose a color other than white.
{T}: Add {W} or one mana of the chosen color.

Thraben Inspector

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

Island

Floodhound

{3}, {T}: Investigate. (Create a Clue token. It's an artifact with "{2}, Sacrifice this artifact: Draw a card.")

Reliquary Tower

You have no maximum hand size.
{T}: Add {C}.

Urza's Tower

{T}: Add {C}. If you control an Urza's Mine and an Urza's Power-Plant, add {C}{C}{C} instead.

Ethersworn Sphinx

Affinity for artifacts (This spell costs {1} less to cast for each artifact you control.)
Flying
Cascade (When you cast this spell, exile cards from the top of your library until you exile a nonland card with lesser mana value. You may cast it without paying its mana cost. Put the exiled cards on the bottom in a random order.)

Bronze Guardian

Double strike
Ward {2} (Whenever this creature becomes the target of a spell or ability an opponent controls, counter it unless that player pays {2}.)
Other artifacts you control have ward {2}.
Bronze Guardian's power is equal to the number of artifacts you control.

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.

Glacian, Powerstone Engineer

{T}, Tap X untapped artifacts you control: Look at the top X cards of your library. Put one of those cards into your hand and the rest into your graveyard.
Partner (You can have two commanders if both have partner.)

Fleeting Memories

When Fleeting Memories enters, investigate. (Create a Clue token. It's an artifact with "{2}, Sacrifice this artifact: Draw a card.")
Whenever you sacrifice a Clue, target player mills three cards.

Urza's Mine

{T}: Add {C}. If you control an Urza's Power-Plant and an Urza's Tower, add {C}{C} instead.

Flood Plain

Flood Plain enters tapped.
{T}, Sacrifice Flood Plain: Search your library for a Plains or Island card, put it onto the battlefield, then shuffle.

Renowned Weaponsmith

{T}: Add {C}{C}. Spend this mana only to cast artifact spells or activate abilities of artifacts.
{U}, {T}: Search your library for a card named Heart-Piercer Bow or Vial of Dragonfire, reveal it, put it into your hand, then shuffle.

Hard Evidence

Create a 0/3 blue Crab creature token.
Investigate. (Create a Clue token. It's an artifact with "{2}, Sacrifice this artifact: Draw a card.")

Command Tower

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

Urza's Power Plant

{T}: Add {C}. If you control an Urza's Mine and an Urza's Tower, add {C}{C} instead.

Academy Manufactor

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

Plains

Treasure Vault

{T}: Add {C}.
{X}{X}, {T}, Sacrifice Treasure Vault: Create X Treasure tokens.

Azorius Chancery

Azorius Chancery enters tapped.
When Azorius Chancery enters, return a land you control to its owner's hand.
{T}: Add {W}{U}.

Great Hall of the Citadel

{T}: Add {C}.
{1}, {T}: Add two mana in any combination of colors. Spend this mana only to cast legendary spells.

Mondrak, Glory Dominus

If one or more tokens would be created under your control, twice that many of those tokens are created instead.
{1}{W/P}{W/P}, Sacrifice two other artifacts and/or creatures: Put an indestructible counter on Mondrak, Glory Dominus. ({W/P} can be paid with either {W} or 2 life.)

Zhalfirin Void

When Zhalfirin Void enters, scry 1. (Look at the top card of your library. You may put that card on the bottom.)
{T}: Add {C}.

Get Lost

Destroy target creature, enchantment, or planeswalker. Its controller creates two Map tokens. (They're artifacts with "{1}, {T}, Sacrifice this artifact: Target creature you control explores. Activate only as a sorcery.")

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

Bearer of Overwhelming Truths

Prowess (Whenever you cast a noncreature spell, this creature gets +1/+1 until end of turn.)
Whenever Bearer of Overwhelming Truths deals combat damage to a player, investigate. (Create a Clue token. It's an artifact with "{2}, Sacrifice this artifact: Draw a card.")

Daring Sleuth

When you sacrifice a Clue, transform Daring Sleuth.

Daring Sleuth // Bearer of Overwhelming Truths

Deserted Beach

Deserted Beach enters tapped unless you control two or more other lands.
{T}: Add {W} or {U}.

Angelic Sleuth

Flying
Whenever another permanent you control leaves the battlefield, if it had counters on it, investigate. (Create a colorless Clue artifact token with "{2}, Sacrifice this artifact: Draw a card.")

Cavern of Souls

As Cavern of Souls enters, choose a creature type.
{T}: Add {C}.
{T}: Add one mana of any color. Spend this mana only to cast a creature spell of the chosen type, and that spell can't be countered.

Eiganjo, Seat of the Empire

{T}: Add {W}.
Channel — {2}{W}, Discard Eiganjo, Seat of the Empire: It deals 4 damage to target attacking or blocking creature. This ability costs {1} less to activate for each legendary creature you control.

Hallowed Fountain

({T}: Add {W} or {U}.)
As Hallowed Fountain enters, you may pay 2 life. If you don't, it enters tapped.

Jhoira's Familiar

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

Darksteel Citadel

Assert Authority

Affinity for artifacts (This spell costs {1} less to cast for each artifact you control.)
Counter target spell. If that spell is countered this way, exile it instead of putting it into its owner's graveyard.

Hall of Storm Giants

If you control two or more other lands, Hall of Storm Giants enters tapped.
{T}: Add {U}.
{5}{U}: Until end of turn, Hall of Storm Giants becomes a 7/7 blue Giant creature with ward {3}. It's still a land. (Whenever it becomes the target of a spell or ability an opponent controls, counter it unless that player pays {3}.)

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.

Indomitable Archangel

Flying
Metalcraft — Artifacts you control have shroud as long as you control three or more artifacts. (An artifact with shroud can't be the target of spells or abilities.)

Thorough Investigation

Whenever you attack, investigate. (Create a Clue token. It's an artifact with "{2}, Sacrifice this artifact: Draw a card.")
Whenever you sacrifice a Clue, venture into the dungeon. (Enter the first room or advance to the next room.)

Thoughtcast

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

Wojek Investigator

Flying, vigilance
At the beginning of your upkeep, investigate once for each opponent who has more cards in hand than you. (To investigate, create a Clue token. It's an artifact with "{2}, Sacrifice this artifact: Draw a card.")

Mirrex

{T}: Add {C}.
{T}: Add one mana of any color. Activate only if Mirrex entered this turn.
{3}, {T}: Create a 1/1 colorless Phyrexian Mite artifact creature token with toxic 1 and "This creature can't block." (Players dealt combat damage by it also get a poison counter.)

Thought Monitor

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

Mox Opal

Metalcraft — {T}: Add one mana of any color. Activate only if you control three or more artifacts.

Sarah Jane Smith

Whenever you cast a historic spell, investigate. This ability triggers only once each turn. (Artifacts, legendaries, and Sagas are historic. To investigate, create a Clue token. It's an artifact with "{2}, Sacrifice this artifact: Draw a card.")
Doctor's companion (You can have two commanders if the other is the Doctor.)

No Witnesses

Each player who controls the most creatures investigates. Then destroy all creatures. (To investigate, create a Clue token. It's an artifact with "{2}, Sacrifice this artifact: Draw a card.")

Mechanized Production

Enchant artifact you control
At the beginning of your upkeep, create a token that's a copy of enchanted artifact. Then if you control eight or more artifacts with the same name as one another, you win the game.

Plaza of Heroes

{T}: Add {C}.
{T}: Add one mana of any color. Spend this mana only to cast a legendary spell.
{T}: Add one mana of any color among legendary permanents you control.
{3}, {T}, Exile Plaza of Heroes: Target legendary creature gains hexproof and indestructible until end of turn.

Broodstar

Affinity for artifacts (This spell costs {1} less to cast for each artifact you control.)
Flying
Broodstar's power and toughness are each equal to the number of artifacts you control.

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}.

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.")

Osgood, Operation Double

When you cast this spell, create a token that's a copy of it, except it isn't legendary.
{T}: Add {C}. Spend this mana only to cast an artifact spell or activate an ability of an artifact.
Paradox — Whenever you cast a spell from anywhere other than your hand, investigate. (Create a Clue token. It's an artifact with "{2}, Sacrifice this artifact: Draw a card.")

Glimmervoid

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

Search the Premises

Whenever a creature attacks you or a planeswalker you control, investigate. (Create a Clue token. It's an artifact with "{2}, Sacrifice this artifact: Draw a card.")

Nyssa of Traken

You have no maximum hand size.
Sonic Booster — Whenever Nyssa of Traken attacks, sacrifice any number of artifacts. When you sacrifice one or more artifacts this way, tap up to that many target creatures and draw that many cards.
Doctor's companion (You can have two commanders if the other is the Doctor.)

Case of the Filched Falcon

When this Case enters, investigate. (Create a Clue token. It's an artifact with "{2}, Sacrifice this artifact: Draw a card.")
To solve — You control three or more artifacts. (If unsolved, solve at the beginning of your end step.)
Solved — {2}{U}, Sacrifice this Case: Put four +1/+1 counters on target noncreature artifact. It becomes a 0/0 Bird creature with flying in addition to its other types.

Field of Ruin

{T}: Add {C}.
{2}, {T}, Sacrifice Field of Ruin: Destroy target nonbasic land an opponent controls. Each player searches their library for a basic land card, puts it onto the battlefield, then shuffles.

Merchant of Truth

Flying
Whenever a nontoken creature you control dies, investigate.
Clues you control have exalted. (Whenever a creature you control attacks alone, that creature gets +1/+1 until end of turn for each instance of exalted among permanents 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.")

Ardent Recruit

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

Adarkar Wastes

{T}: Add {C}.
{T}: Add {W} or {U}. Adarkar Wastes deals 1 damage to you.

Darksteel Forge

Artifacts you control have indestructible. (Effects that say "destroy" don't destroy them. Artifact creatures with indestructible can't be destroyed by damage.)

Fabled Passage

{T}, Sacrifice Fabled Passage: Search your library for a basic land card, put it onto the battlefield tapped, then shuffle. Then if you control four or more lands, untap that land.

Adaptive Gemguard

Tap two untapped artifacts and/or creatures you control: Put a +1/+1 counter on Adaptive Gemguard. Activate only as a sorcery.

Fateful Absence

Destroy target creature or planeswalker. Its controller investigates. (Create a Clue token. It's an artifact with "{2}, Sacrifice this artifact: Draw a card.")

Gateway Plaza

Gateway Plaza enters tapped.
When Gateway Plaza enters, sacrifice it unless you pay {1}.
{T}: Add one mana of any color.

Elder Owyn Lyons

Artifacts you control have ward {1}. (Whenever an artifact you control becomes the target of a spell or ability an opponent controls, counter it unless that player pays {1}.)
When Elder Owyn Lyons enters or dies, return target artifact card from your graveyard to your hand.

Glacial Floodplain

({T}: Add {W} or {U}.)
Glacial Floodplain enters tapped.

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.

Temple of the False God

{T}: Add {C}{C}. Activate only if you control five or more lands.

Dennick, Pious Apparition

Flying
Whenever one or more creature cards are put into graveyards from anywhere, investigate. This ability triggers only once each turn. (Create a Clue token. It's an artifact with "{2}, Sacrifice this artifact: Draw a card.")
If Dennick, Pious Apparition would be put into a graveyard from anywhere, exile it instead.

Dennick, Pious Apprentice

Lifelink
Cards in graveyards can't be the targets of spells or abilities.
Disturb {2}{W}{U} (You may cast this card from your graveyard transformed for its disturb cost.)

Dennick, Pious Apprentice // Dennick, Pious Apparition

Celestial Colonnade

Celestial Colonnade enters tapped.
{T}: Add {W} or {U}.
{3}{W}{U}: Until end of turn, Celestial Colonnade becomes a 4/4 white and blue Elemental creature with flying and vigilance. It's still a land.