Silver Myr

Rewind

Counter target spell. Untap up to four lands.

Mana Severance

Search your library for any number of land cards, exile them, then shuffle.

Muddle the Mixture

Counter target instant or sorcery spell.
Transmute {1}{U}{U} ({1}{U}{U}, Discard this card: Search your library for a card with the same mana value as this card, reveal it, put it into your hand, then shuffle. Transmute only as a sorcery.)

Laboratory Maniac

If you would draw a card while your library has no cards in it, you win the game instead.

Will of the Naga

Delve (Each card you exile from your graveyard while casting this spell pays for {1}.)
Tap up to two target creatures. Those creatures don't untap during their controller's next untap step.

Set Adrift

Delve (Each card you exile from your graveyard while casting this spell pays for {1}.)
Put target nonland permanent on top of its owner's library.

Archaeomancer

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

Counterspell

Mystical Tutor

Search your library for an instant or sorcery card, reveal it, then shuffle and put that card on top.

High Tide

Until end of turn, whenever a player taps an Island for mana, that player adds an additional {U}.

Insectile Aberration

Delver of Secrets

At the beginning of your upkeep, look at the top card of your library. You may reveal that card. If an instant or sorcery card is revealed this way, transform Delver of Secrets.

Delver of Secrets // Insectile Aberration

Flow of Knowledge

Draw a card for each Island you control, then discard two cards.

Dig Through Time

Delve (Each card you exile from your graveyard while casting this spell pays for {1}.)
Look at the top seven cards of your library. Put two of them into your hand and the rest on the bottom of your library in any order.

Negate

Ornithopter of Paradise

Engulf the Shore

Return to their owners' hands all creatures with toughness less than or equal to the number of Islands you control.

Windfall

Each player discards their hand, then draws cards equal to the greatest number of cards a player discarded this way.

Treasure Cruise

Delve (Each card you exile from your graveyard while casting this spell pays for {1}.)
Draw three cards.

Thought Scour

Target player mills two cards.
Draw a card.

Brainstorm

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

Salvager of Secrets

When Salvager of Secrets enters, return target instant or sorcery card from your graveyard to your hand.

Frantic Search

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

Mnemonic Wall

Defender
When Mnemonic Wall enters, you may return target instant or sorcery card from your graveyard to your hand.

Rite of Undoing

Delve (Each card you exile from your graveyard while casting this spell pays for {1}.)
Return target nonland permanent you control and target nonland permanent you don't control to their owners' hands.

Selective Memory

Search your library for any number of nonland cards, exile them, then shuffle.

Jace, Wielder of Mysteries

If you would draw a card while your library has no cards in it, you win the game instead.
+1: Target player mills two cards. Draw a card.
−8: Draw seven cards. Then if your library has no cards in it, you win the game.

Solve the Equation

Search your library for an instant or sorcery card, reveal it, put it into your hand, then shuffle.

Shipwreck Dowser

Prowess (Whenever you cast a noncreature spell, this creature gets +1/+1 until end of turn.)
When Shipwreck Dowser enters, return target instant or sorcery card from your graveyard to your hand.

Leveler

When Leveler enters, exile all cards from your library.

Gale, Waterdeep Prodigy

Whenever you cast an instant or sorcery spell from your hand, you may cast up to one target card of the other type from your graveyard. If a spell cast from your graveyard this way would be put into your graveyard, exile it instead.
Choose a Background (You can have a Background as a second commander.)

Scribe of the Mindful

{1}, {T}, Sacrifice Scribe of the Mindful: Return target instant or sorcery card from your graveyard to your hand.

Dispel

Thassa's Oracle

When Thassa's Oracle enters, look at the top X cards of your library, where X is your devotion to blue. Put up to one of them on top of your library and the rest on the bottom of your library in a random order. If X is greater than or equal to the number of cards in your library, you win the game. (Each {U} in the mana costs of permanents you control counts toward your devotion to blue.)

Ponder

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

Island

Logic Knot

Delve (Each card you exile from your graveyard while casting this spell pays for {1}.)
Counter target spell unless its controller pays {X}.