Part the Veil

Return all creatures you control to their owner's hand.

Eerie Procession

Search your library for an Arcane card, reveal that card, put it into your hand, then shuffle.

Cloudhoof Kirin

Flying
Whenever you cast a Spirit or Arcane spell, you may have target player mill X cards, where X is that spell's mana value.

Peer Through Depths

Look at the top five cards of your library. You may reveal an instant or sorcery card from among them and put it into your hand. Put the rest on the bottom of your library in any order.

Kiri-Onna

When Kiri-Onna enters, return target creature to its owner's hand.
Whenever you cast a Spirit or Arcane spell, you may return Kiri-Onna to its owner's hand.

Tomorrow, Azami's Familiar

If you would draw a card, look at the top three cards of your library instead. Put one of those cards into your hand and the rest on the bottom of your library in any order.

Stream of Consciousness

Target player shuffles up to four target cards from their graveyard into their library.

Sire of the Storm

Flying
Whenever you cast a Spirit or Arcane spell, you may draw a card.

Ribbons of the Reikai

Teller of Tales

Flying
Whenever you cast a Spirit or Arcane spell, you may tap or untap target creature.

Reach Through Mists

Eye of Nowhere

Return target permanent to its owner's hand.

Reweave

Target permanent's controller sacrifices it. If the player does, they reveal cards from the top of their library until they reveal a permanent card that shares a card type with the sacrificed permanent, put that card onto the battlefield, then shuffle.
Splice onto Arcane {2}{U}{U} (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.)

Long-Forgotten Gohei

Arcane spells you cast cost {1} less to cast.
Spirit creatures you control get +1/+1.

Petals of Insight

Look at the top three cards of your library. You may put those cards on the bottom of your library in any order. If you do, return Petals of Insight to its owner's hand. Otherwise, draw three cards.

Murmurs from Beyond

Reveal the top three cards of your library. An opponent chooses one of them. Put that card into your graveyard and the rest into your hand.

Ideas Unbound

Draw three cards. Discard three cards at the beginning of the next end step.

Baku Altar

Whenever you cast a Spirit or Arcane spell, you may put a ki counter on Baku Altar.
{2}, {T}, Remove a ki counter from Baku Altar: Create a 1/1 colorless Spirit creature token.

Sift Through Sands

Draw two cards, then discard a card.
If you've cast a spell named Peer Through Depths and a spell named Reach Through Mists this turn, you may search your library for a card named The Unspeakable, put it onto the battlefield, then shuffle.

Veil of Secrecy

Target creature gains shroud until end of turn and can't be blocked this turn. (A creature with shroud can't be the target of spells or abilities.)
Splice onto Arcane—Return a blue creature you control to its owner's hand. (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.)

The Unspeakable

Flying, trample
Whenever The Unspeakable deals combat damage to a player, you may return target Arcane card from your graveyard to your hand.

Evermind

(Nonexistent mana costs can't be paid.)
Draw a card.
Splice onto Arcane {1}{U} (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.)

Consuming Vortex

Return target creature to its owner's hand.
Splice onto Arcane {3}{U} (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.)

Rattlechains

Flash
Flying
When Rattlechains enters, target Spirit gains hexproof until end of turn.
You may cast Spirit spells as though they had flash.