Counter target spell. That spell's controller may draw a card.

Prophetic Prism

When Prophetic Prism enters, draw a card.
{1}, {T}: Add one mana of any color.

Wedding Invitation

When Wedding Invitation enters, draw a card.
{T}, Sacrifice Wedding Invitation: Target creature can't be blocked this turn. If it's a Vampire, it also gains lifelink until end of turn.

Decanter of Endless Water

You have no maximum hand size.
{T}: Add one mana of any color.

Alchemist's Vial

When Alchemist's Vial enters, draw a card.
{1}, {T}, Sacrifice Alchemist's Vial: Target creature can't attack or block this turn.

Prizefighter Construct

Spare Supplies

Spare Supplies enters tapped.
When Spare Supplies enters, draw a card.
{2}, {T}, Sacrifice Spare Supplies: Draw a card.

Scry 1. (Look at the top card of your library. You may put that card on the bottom.)
Draw a card.

Escaped Experiment

Whenever Escaped Experiment attacks, target creature an opponent controls gets -X/-0 until end of turn, where X is the number of artifacts you control.

Aeronaut's Wings

Equipped creature gets +1/+0 and has flying.
Equip {2} ({2}: Attach to target creature you control. Equip only as a sorcery.)

Goldvein Pick

Equipped creature gets +1/+1.
Whenever equipped creature deals combat damage to a player, create a Treasure token. (It's an artifact with "{T}, Sacrifice this token: Add one mana of any color.")
Equip {1} ({1}: Attach to target creature you control. Equip only as a sorcery.)

Skyscanner

Flying
When Skyscanner enters, draw a card.

Anticipate

Look at the top three cards of your library. Put one of them into your hand and the rest on the bottom of your library in any order.

Juggernaut

This creature attacks each combat if able.
This creature can't be blocked by Walls.

Runed Stalactite

Equipped creature gets +1/+1 and is every creature type.
Equip {2}

Gearsmith Guardian

Gearsmith Guardian gets +2/+0 as long as you control a blue creature.

untouchable

Marching Duodrone

Whenever Marching Duodrone attacks, each player creates a Treasure token. (It's an artifact with "{T}, Sacrifice this artifact: Add one mana of any color.")

Urza, Powerstone Prodigy

Vigilance
{1}, {T}: Draw a card, then discard a card.
Whenever you discard one or more artifact cards, create a tapped Powerstone token. This ability triggers only once each turn. (The token is an artifact with "{T}: Add {C}. This mana can't be spent to cast a nonartifact spell.")

Dune Mover

Toxic 1 (Players dealt combat damage by this creature also get a poison counter.)
When Dune Mover enters, you may search your library for a basic land card, reveal it, then shuffle and put that card on top.

Short Sword

Equipped creature gets +1/+1.
Equip {1} ({1}: Attach to target creature you control. Equip only as a sorcery.)

Commander's Sphere

{T}: Add one mana of any color in your commander's color identity.
Sacrifice Commander's Sphere: Draw a card.

Steelclad Serpent

Steelclad Serpent can't attack unless you control another artifact.

Spell Pierce

Counter target noncreature spell unless its controller pays {2}.

Traveler's Amulet

{1}, Sacrifice Traveler's Amulet: Search your library for a basic land card, reveal it, put it into your hand, then shuffle.

Frantic Search

Draw two cards, then discard two cards. Untap up to three lands.

Preordain

Scry 2, then draw a card. (To scry 2, look at the top two cards of your library, then put any number of them on the bottom and the rest on top in any order.)

Paragon of Modernity

Flying
{3}: Paragon of Modernity gets +1/+1 until end of turn. If exactly three colors of mana were spent to activate this ability, put a +1/+1 counter on it instead.

Supply Drop

Flash
When Supply Drop enters, target creature you control gets +2/+2 until end of turn.
{4}, {T}, Sacrifice Supply Drop: Draw a card.

Sky Diamond

Snap

Return target creature to its owner's hand. Untap up to two lands.

Campus Guide

When this creature enters, you may search your library for a basic land card, reveal it, then shuffle and put that card on top.

Mimic

{T}, Sacrifice Mimic: Add one mana of any color.
{2}: Mimic becomes a Shapeshifter artifact creature with base power and toughness 3/3 until end of turn.

Pristine Talisman

Shield-Wall Sentinel

Defender
When Shield-Wall Sentinel enters, you may search your library for a creature card with defender, reveal it, put it into your hand, then shuffle.

Koilos Roc

Flash
Flying
When Koilos Roc enters, create a tapped Powerstone token. (It's an artifact with "{T}: Add {C}. This mana can't be spent to cast a nonartifact spell.")

Foundry Inspector

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

Scroll of Avacyn

{1}, Sacrifice Scroll of Avacyn: Draw a card. If you control an Angel, you gain 5 life.

Armory of Iroas

Whenever equipped creature attacks, put a +1/+1 counter on it.
Equip {2} ({2}: Attach to target creature you control. Equip only as a sorcery.)

Prized Statue

When Prized Statue enters or is put into a graveyard from the battlefield, create a Treasure token. (It's an artifact with "{T}, Sacrifice this artifact: Add one mana of any color.")

Wizard Mentor

{T}: Return Wizard Mentor and target creature you control to their owner's hand.

Elite Instructor

When Elite Instructor enters, draw a card, then discard a card.

Ornithopter

Tocasia's Dig Site

{T}: Add {C}.
{3}, {T}: Surveil 1. (Look at the top card of your library. You may put it into your graveyard.)

Mind Stone

{T}: Add {C}.
{1}, {T}, Sacrifice Mind Stone: Draw a card.

Anodet Lurker

When Anodet Lurker dies, you gain 3 life.

Mine Worker

{T}: You gain 1 life. If you control creatures named Power Plant Worker and Tower Worker, you gain 3 life instead.

Lofty Denial

Counter target spell unless its controller pays {1}. If you control a creature with flying, counter that spell unless its controller pays {4} instead.

Ichor Wellspring

When Ichor Wellspring enters or is put into a graveyard from the battlefield, draw a card.

Island

Self-Assembler

When Self-Assembler enters, you may search your library for an Assembly-Worker creature card, reveal it, put it into your hand, then shuffle.

Workshop Assistant

When Workshop Assistant dies, return another target artifact card from your graveyard to your hand.

Howling Golem

Whenever Howling Golem attacks or blocks, each player draws a card.

Dragon Engine

{2}: Dragon Engine gets +1/+0 until end of turn.

Dutiful Replicator

When Dutiful Replicator enters, you may pay {1}. When you do, create a token that's a copy of target token you control not named Dutiful Replicator.

Depth Charge Colossus

Prototype {4}{U}{U} — 6/6 (You may cast this spell with different mana cost, color, and size. It keeps its abilities and types.)
Depth Charge Colossus doesn't untap during your untap step.
{3}: Untap Depth Charge Colossus.

Sleeper Dart

When Sleeper Dart enters, draw a card.
{T}, Sacrifice Sleeper Dart: Target creature doesn't untap during its controller's next untap step.

Golem-Skin Gauntlets

Equipped creature gets +1/+0 for each Equipment attached to it.
Equip {2} ({2}: Attach to target creature you control. Equip only as a sorcery. This card enters unattached and stays on the battlefield if the creature leaves.)

Amorphous Axe

Equipped creature gets +3/+0 and is every creature type.
Equip {3} ({3}: Attach to target creature you control. Equip only as a sorcery.)

Guardians of Koilos

When Guardians of Koilos enters, you may return another target historic permanent you control to its owner's hand. (Artifacts, legendaries, and Sagas are historic.)

Deep Analysis

Target player draws two cards.
Flashback—{1}{U}, Pay 3 life. (You may cast this card from your graveyard for its flashback cost. Then exile it.)

Maelstrom Colossus

Cascade (When you cast this spell, exile cards from the top of your library until you exile a nonland card that costs less. You may cast it without paying its mana cost. Put the exiled cards on the bottom in a random order.)

Golden Egg

When Golden Egg enters, draw a card.
{1}, {T}, Sacrifice Golden Egg: Add one mana of any color.
{2}, {T}, Sacrifice Golden Egg: You gain 3 life.

Tower Worker

Reach
{T}: Add {C}. If you control creatures named Mine Worker and Power Plant Worker, add {C}{C}{C} instead.

Raven Wings

Equipped creature gets +1/+0, has flying, and is a Bird in addition to its other types.
Equip {2} ({2}: Attach to target creature you control. Equip only as a sorcery.)

Foundry Assembler

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

Peregrine Drake

Flying
When Peregrine Drake enters, untap up to five lands.

Merfolk Pupil

When Merfolk Pupil enters, draw a card, then discard a card.
{1}{U}, Exile Merfolk Pupil from your graveyard: Draw a card, then discard a card.

Pierce Strider

When Pierce Strider enters, target opponent loses 3 life.

Aquamoeba

Discard a card: Switch Aquamoeba's power and toughness until end of turn.

Surgical Skullbomb

{1}, Sacrifice Surgical Skullbomb: Draw a card.
{2}{U}, Sacrifice Surgical Skullbomb: Return target creature to its owner's hand. Draw a card. Activate only as a sorcery.

Swiftgear Drake

Flying, haste
When Swiftgear Drake enters, put up to one target card from a graveyard on the bottom of its owner's library.

Power Plant Worker

{3}: Power Plant Worker gets +2/+2 until end of turn. If you control creatures named Mine Worker and Tower Worker, put two +1/+1 counters on Power Plant Worker instead. Activate only once each turn.

Aether Spellbomb

{U}, Sacrifice Aether Spellbomb: Return target creature to its owner's hand.
{1}, Sacrifice Aether Spellbomb: Draw a card.

Bronze Sword

Equipped creature gets +2/+0.
Equip {3} ({3}: Attach to target creature you control. Equip only as a sorcery.)