Willbreaker

Whenever a creature an opponent controls becomes the target of a spell or ability you control, gain control of that creature for as long as you control Willbreaker.

Psychic Corrosion

Whenever you draw a card, each opponent mills two cards.

Powerbalance

Whenever an opponent casts a spell, you may reveal the top card of your library. If you do, you may cast that card without paying its mana cost if the two spells have the same mana value.

Expedite

Target creature gains haste until end of turn.
Draw a card.

Balmor, Battlemage Captain

Flying
Whenever you cast an instant or sorcery spell, creatures you control get +1/+0 and gain trample until end of turn.

Sapphire Medallion

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

Essence Flux

Exile target creature you control, then return that card to the battlefield under its owner's control. If it's a Spirit, put a +1/+1 counter on it.

Arcanis the Omnipotent

{T}: Draw three cards.
{2}{U}{U}: Return Arcanis the Omnipotent to its owner's hand.

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.)

Island

Slip Through Space

Devoid (This card has no color.)
Target creature can't be blocked this turn.
Draw a card.

Cephalid Constable

Whenever Cephalid Constable deals combat damage to a player, return up to that many target permanents that player controls to their owner's hand.

Stonybrook Banneret

Islandwalk (This creature can't be blocked as long as defending player controls an Island.)
Merfolk spells and Wizard spells you cast cost {1} less to cast.

Adeliz, the Cinder Wind

Flying, haste
Whenever you cast an instant or sorcery spell, Wizards you control get +1/+1 until end of turn.

Murmuring Mystic

Whenever you cast an instant or sorcery spell, create a 1/1 blue Bird Illusion creature token with flying.

Dreadhorde Arcanist

Trample
Whenever Dreadhorde Arcanist attacks, you may cast target instant or sorcery card with mana value less than or equal to Dreadhorde Arcanist's power from your graveyard without paying its mana cost. If that spell would be put into your graveyard, exile it instead.

Thought Reflection

If you would draw a card, draw two cards instead.

Goblin Electromancer

Instant and sorcery spells you cast cost {1} less to cast.

Ruby Medallion

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

Azami, Lady of Scrolls

Tap an untapped Wizard you control: Draw a card.

Baral, Chief of Compliance

Instant and sorcery spells you cast cost {1} less to cast.
Whenever a spell or ability you control counters a spell, you may draw a card. If you do, discard a card.

Cryptic Gateway

Tap two untapped creatures you control: You may put a creature card from your hand that shares a creature type with each creature tapped this way onto the battlefield.

Talrand, Sky Summoner

Whenever you cast an instant or sorcery spell, create a 2/2 blue Drake creature token with flying.

Ruination

Seal of the Guildpact

As Seal of the Guildpact enters, choose two colors.
Each spell you cast costs {1} less to cast for each of the chosen colors it is.

Kari Zev's Expertise

Gain control of target creature or Vehicle until end of turn. Untap it. It gains haste until end of turn.
You may cast a spell with mana value 2 or less from your hand without paying its mana cost.

Naban, Dean of Iteration

If a Wizard you control entering causes a triggered ability of a permanent you control to trigger, that ability triggers an additional time.

Ponder

Look at the top three cards of your library, then put them back in any order. You may shuffle.
Draw a card.

Arjun, the Shifting Flame

Flying
Whenever you cast a spell, put the cards in your hand on the bottom of your library in any order, then draw that many cards.

Mindmoil

Whenever you cast a spell, put the cards in your hand on the bottom of your library in any order, then draw that many cards.

Mountain

Scholar of the Ages

When Scholar of the Ages enters, return up to two target instant and/or sorcery cards from your graveyard to your hand.

Serum Visions

Patron Wizard

Tap an untapped Wizard you control: Counter target spell unless its controller pays {1}.

Galecaster Colossus

Tap an untapped Wizard you control: Return target nonland permanent you don't control to its owner's hand.

Mitotic Manipulation

Look at the top seven cards of your library. You may put one of those cards onto the battlefield if it has the same name as a permanent. Put the rest on the bottom of your library in any order.

Intruder Alarm

Creatures don't untap during their controllers' untap steps.
Whenever a creature enters, untap all creatures.

Sunbird's Invocation

Whenever you cast a spell from your hand, reveal the top X cards of your library, where X is that spell's mana value. You may cast a spell with mana value X or less from among cards revealed this way without paying its mana cost. Put the rest on the bottom of your library in a random order.

Umara Mystic

Flying
Whenever you cast an instant, sorcery, or Wizard spell, Umara Mystic gets +2/+0 until end of turn.

Archaeomancer

When Archaeomancer enters, return target instant or sorcery card from your graveyard to your hand.

Kindred Discovery

As Kindred Discovery enters, choose a creature type.
Whenever a creature you control of the chosen type enters or attacks, draw a card.

Flashfires

Brainstorm

Draw three cards, then put two cards from your hand on top of your library in any order.

Impact Tremors

Whenever a creature you control enters, Impact Tremors deals 1 damage to each opponent.