Daretti, Scrap Savant

+2: Discard up to two cards, then draw that many cards.
−2: Sacrifice an artifact. If you do, return target artifact card from your graveyard to the battlefield.
−10: You get an emblem with "Whenever an artifact is put into your graveyard from the battlefield, return that card to the battlefield at the beginning of the next end step."
Daretti, Scrap Savant can be your commander.

Ricochet Trap

If an opponent cast a blue spell this turn, you may pay {R} rather than pay this spell's mana cost.
Change the target of target spell with a single target.

Sensei's Divining Top

{1}: Look at the top three cards of your library, then put them back in any order.
{T}: Draw a card, then put Sensei's Divining Top on top of its owner's library.

Mana Seism

Sacrifice any number of lands, then add that much {C}.

Mana Geyser

Add {R} for each tapped land your opponents control.

Cathartic Reunion

As an additional cost to cast this spell, discard two cards.
Draw three cards.

Welding Jar

Sacrifice Welding Jar: Regenerate target artifact.

Goblin Cratermaker

{1}, Sacrifice Goblin Cratermaker: Choose one —
• Goblin Cratermaker deals 2 damage to target creature.
• Destroy target colorless nonland permanent.

Fractured Powerstone

{T}: Add {C}.
{T}: Roll the planar die. Activate only as a sorcery.

Mind Stone

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

Abrade

Choose one —
• Abrade deals 3 damage to target creature.
• Destroy target artifact.

Helm of the Host

At the beginning of combat on your turn, create a token that's a copy of equipped creature, except the token isn't legendary. That token gains haste.
Equip {5}

Red Elemental Blast

Choose one —
• Counter target blue spell.
• Destroy target blue permanent.

Jeska's Will

Choose one. If you control a commander as you cast this spell, you may choose both instead.
• Add {R} for each card in target opponent's hand.
• Exile the top three cards of your library. You may play them this turn.

Irencrag Feat

Add seven {R}. You can cast only one more spell this turn.

Deflecting Swat

If you control a commander, you may cast this spell without paying its mana cost.
You may choose new targets for target spell or ability.

Into the Fire

Choose one —
• Into the Fire deals 2 damage to each creature, planeswalker, and battle.
• Put any number of cards from your hand on the bottom of your library, then draw that many cards plus one.

Simian Spirit Guide

Exile Simian Spirit Guide from your hand: Add {R}.

Myr Retriever

When Myr Retriever dies, return another target artifact card from your graveyard to your hand.

Mishra, Excavation Prodigy

Haste
{1}, {T}, Discard a card: Draw a card.
Whenever you discard one or more artifact cards, add {R}{R}. This ability triggers only once each turn.

Imperial Recruiter

When Imperial Recruiter enters, search your library for a creature card with power 2 or less, reveal it, put it into your hand, then shuffle.

Geosurge

Add {R}{R}{R}{R}{R}{R}{R}. Spend this mana only to cast artifact or creature spells.

Seething Song

Jeweled Lotus

{T}, Sacrifice Jeweled Lotus: Add three mana of any one color. Spend this mana only to cast your commander.

Heart of Ramos

{T}: Add {R}.
Sacrifice Heart of Ramos: Add {R}.

Akki Ronin

Whenever a Samurai or Warrior you control attacks alone, you may discard a card. If you do, draw a card.

Pyretic Ritual

Gamble

Search your library for a card, put that card into your hand, discard a card at random, then shuffle.

Brass Squire

{T}: Attach target Equipment you control to target creature you control.

Palladium Myr

Prismatic Lens

{T}: Add {C}.
{1}, {T}: Add one mana of any color.

Gilded Lotus

Arcane Signet

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

Sol Ring

Reckless Barbarian

Sacrifice Reckless Barbarian: Add {R}{R}.

Trash for Treasure

As an additional cost to cast this spell, sacrifice an artifact.
Return target artifact card from your graveyard to the battlefield.

Lotus Petal

{T}, Sacrifice Lotus Petal: Add one mana of any color.

Sweltering Suns

Sweltering Suns deals 3 damage to each creature.
Cycling {3} ({3}, Discard this card: Draw a card.)

Chaos Warp

The owner of target permanent shuffles it into their library, then reveals the top card of their library. If it's a permanent card, they put it onto the battlefield.

Rite of Flame

Add {R}{R}, then add {R} for each card named Rite of Flame in each graveyard.

Godo, Bandit Warlord

When Godo, Bandit Warlord enters, you may search your library for an Equipment card, put it onto the battlefield, then shuffle.
Whenever Godo attacks for the first time each turn, untap it and all Samurai you control. After this phase, there is an additional combat phase.

Iron Myr

Professional Face-Breaker

Menace
Whenever one or more creatures you control deal combat damage to a player, create a Treasure token.
Sacrifice a Treasure: Exile the top card of your library. You may play that card this turn.

Vandalblast

Destroy target artifact you don't control.
Overload {4}{R} (You may cast this spell for its overload cost. If you do, change "target" in its text to "each.")

Treasonous Ogre

Dethrone (Whenever this creature attacks the player with the most life or tied for most life, put a +1/+1 counter on it.)
Pay 3 life: Add {R}.

Blasphemous Act

This spell costs {1} less to cast for each creature on the battlefield.
Blasphemous Act deals 13 damage to each creature.

Big Score

As an additional cost to cast this spell, discard a card.
Draw two cards and create two Treasure tokens. (They're artifacts with "{T}, Sacrifice this artifact: Add one mana of any color.")

Faithless Looting

Draw two cards, then discard two cards.
Flashback {2}{R} (You may cast this card from your graveyard for its flashback cost. Then exile it.)

Burnout

Counter target instant spell if it's blue.
Draw a card at the beginning of the next turn's upkeep.

Fork

Copy target instant or sorcery spell, except that the copy is red. You may choose new targets for the copy.

Mogg Salvage

If an opponent controls an Island and you control a Mountain, you may cast this spell without paying its mana cost.
Destroy target artifact.

Thran Dynamo

Magus of the Wheel

{1}{R}, {T}, Sacrifice Magus of the Wheel: Each player discards their hand, then draws seven cards.

Pyroblast

Choose one —
• Counter target spell if it's blue.
• Destroy target permanent if it's blue.

Goblin Welder

{T}: Choose target artifact a player controls and target artifact card in that player's graveyard. If both targets are still legal as this ability resolves, that player simultaneously sacrifices the artifact and returns the artifact card to the battlefield.

Lotus Bloom

Suspend 3—{0} (Rather than cast this card from your hand, pay {0} and exile it with three time counters on it. At the beginning of your upkeep, remove a time counter. When the last is removed, you may cast it without paying its mana cost.)
{T}, Sacrifice Lotus Bloom: Add three mana of any one color.

Thought Vessel

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

Mountain

Wild Guess

As an additional cost to cast this spell, discard a card.
Draw two cards.

Generator Servant

{T}, Sacrifice Generator Servant: Add {C}{C}. If that mana is spent on a creature spell, it gains haste until end of turn. (That creature can attack and {T} as soon as it comes under your control.)

Hedron Crawler

{T}: Add {C}. ({C} represents colorless mana.)

Hammer of Nazahn

Whenever Hammer of Nazahn or another Equipment you control enters, you may attach that Equipment to target creature you control.
Equipped creature gets +2/+0 and has indestructible.
Equip {4}

Desperate Ritual

Add {R}{R}{R}.
Splice onto Arcane {1}{R} (As you cast an Arcane spell, you may reveal this card from your hand and pay its splice cost. If you do, add this card's effects to that spell.)

Reverberate

Copy target instant or sorcery spell. You may choose new targets for the copy.

Magnetic Theft

Attach target Equipment to target creature. (Control of the Equipment doesn't change.)