Harbinger of Spring

Protection from non-Spirit creatures
Soulshift 4 (When this creature dies, you may return target Spirit card with mana value 4 or less from your graveyard to your hand.)

Iname, Life Aspect

When Iname, Life Aspect dies, you may exile it. If you do, return any number of target Spirit cards from your graveyard to your hand.

Unearthly Blizzard

Up to three target creatures can't block this turn.

Forest

Ember-Fist Zubera

When Ember-Fist Zubera dies, it deals damage to any target equal to the number of Zubera that died this turn.

Frostling

Sacrifice Frostling: It deals 1 damage to target creature.

Yamabushi's Flame

Yamabushi's Flame deals 3 damage to any target. If a creature dealt damage this way would die this turn, exile it instead.

Kami of the Hunt

Whenever you cast a Spirit or Arcane spell, Kami of the Hunt gets +1/+1 until end of turn.

Ichiga, Who Topples Oaks

Trample
Remove a ki counter from Ichiga, Who Topples Oaks: Target creature gets +2/+2 until end of turn.

Budoka Pupil

Whenever you cast a Spirit or Arcane spell, you may put a ki counter on Budoka Pupil.
At the beginning of the end step, if there are two or more ki counters on Budoka Pupil, you may flip it.

Budoka Pupil // Ichiga, Who Topples Oaks

Brutal Deceiver

{1}: Look at the top card of your library.
{2}: Reveal the top card of your library. If it's a land card, Brutal Deceiver gets +1/+0 and gains first strike until end of turn. Activate only once each turn.

Mountain

Kami of Fire's Roar

Whenever you cast a Spirit or Arcane spell, target creature can't block this turn.

Shimatsu the Bloodcloaked

As Shimatsu the Bloodcloaked enters, sacrifice any number of permanents. Shimatsu enters with that many +1/+1 counters on it.

Time of Need

Search your library for a legendary creature card, reveal it, put it into your hand, then shuffle.

Loam Dweller

Whenever you cast a Spirit or Arcane spell, you may put a land card from your hand onto the battlefield tapped.

Child of Thorns

Sacrifice Child of Thorns: Target creature gets +1/+1 until end of turn.

Gnarled Mass

Soilshaper

Whenever you cast a Spirit or Arcane spell, target land becomes a 3/3 creature until end of turn. It's still a land.

Lifespinner

{T}, Sacrifice three Spirits: Search your library for a legendary Spirit permanent card, put it onto the battlefield, then shuffle.

Glacial Ray

Glacial Ray deals 2 damage to any target.
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.)

Rootrunner

{G}{G}, Sacrifice Rootrunner: Put target land on top of its owner's library.
Soulshift 3 (When this creature dies, you may return target Spirit card with mana value 3 or less from your graveyard to your hand.)