Sapphire Medallion

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

Negate

Sol Ring

Deranged Assistant

{T}, Mill a card: Add {C}. (To mill a card, put the top card of your library into your graveyard.)

Millikin

Frantic Search

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

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.

Island

Dreamscape Artist

{2}{U}, {T}, Discard a card, Sacrifice a land: Search your library for up to two basic land cards, put them onto the battlefield, then shuffle.

Sky Diamond

Arcane Signet

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

Archaeomancer

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

Kaho, Minamo Historian

When Kaho, Minamo Historian enters, search your library for up to three instant cards, exile them, then shuffle.
{X}, {T}: You may cast a spell with mana value X from among cards exiled with Kaho without paying its mana cost.

Counterspell

Retraced Image

Reveal a card in your hand, then put that card onto the battlefield if it has the same name as a permanent.

Windfall

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

Essence Scatter

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.

Fact or Fiction

Reveal the top five cards of your library. An opponent separates those cards into two piles. Put one pile into your hand and the other into your graveyard.