Patrician Geist

Flying
Other Spirits you control get +1/+1.
Spells you cast from your graveyard cost {1} less to cast.

Rattlechains

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

Ethereal Valkyrie

Flying
Whenever Ethereal Valkyrie enters or attacks, draw a card, then exile a card from your hand face down. It becomes foretold. Its foretell cost is its mana cost reduced by {2}. (On a later turn, you may cast it for its foretell cost, even if this creature has left the battlefield.)

Oyobi, Who Split the Heavens

Flying
Whenever you cast a Spirit or Arcane spell, create a 3/3 white Spirit creature token with flying.

Selfless Spirit

Flying
Sacrifice Selfless Spirit: Creatures you control gain indestructible until end of turn.

Angel of Flight Alabaster

Flying
At the beginning of your upkeep, return target Spirit card from your graveyard to your hand.

Drogskol Cavalry

Flying
Whenever another Spirit you control enters, you gain 2 life.
{3}{W}: Create a 1/1 white Spirit creature token with flying.

Soulherder

Whenever a creature is exiled from the battlefield, put a +1/+1 counter on Soulherder.
At the beginning of your end step, you may exile another target creature you control, then return that card to the battlefield under its owner's control.

Twilight Drover

Whenever a creature token leaves the battlefield, put a +1/+1 counter on Twilight Drover.
{2}{W}, Remove a +1/+1 counter from Twilight Drover: Create two 1/1 white Spirit creature tokens with flying.

Dreamshackle Geist

Flying
At the beginning of combat on your turn, choose up to one —
• Tap target creature.
• Target creature doesn't untap during its controller's next untap step.

Spectral Arcanist

Flying
When Spectral Arcanist enters, you may cast an instant or sorcery spell with mana value less than or equal to the number of Spirits you control from a graveyard without paying its mana cost. If that spell would be put into a graveyard, exile it instead.

Millicent, Restless Revenant

This spell costs {1} less to cast for each Spirit you control.
Flying
Whenever Millicent, Restless Revenant or another nontoken Spirit you control dies or deals combat damage to a player, create a 1/1 white Spirit creature token with flying.

Kira, Great Glass-Spinner

Flying
Creatures you control have "Whenever this creature becomes the target of a spell or ability for the first time each turn, counter that spell or ability."

Ghostly Pilferer

Whenever Ghostly Pilferer becomes untapped, you may pay {2}. If you do, draw a card.
Whenever an opponent casts a spell from anywhere other than their hand, draw a card.
Discard a card: Ghostly Pilferer can't be blocked this turn.

Priest of the Blessed Graf

At the beginning of your end step, create X 1/1 white Spirit creature tokens with flying, where X is the number of opponents who control more lands than you.

Clarion Spirit

Whenever you cast your second spell each turn, create a 1/1 white Spirit creature token with flying.

Azorius Signet

Guardian of Faith

Flash
Vigilance
When Guardian of Faith enters, any number of other target creatures you control phase out. (Treat them and anything attached to them as though they don't exist until their controller's next turn.)

Mausoleum Wanderer

Flying
Whenever another Spirit you control enters, Mausoleum Wanderer gets +1/+1 until end of turn.
Sacrifice Mausoleum Wanderer: Counter target instant or sorcery spell unless its controller pays {X}, where X is Mausoleum Wanderer's power.

Nikko-Onna

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

Windborn Muse

Flying
Creatures can't attack you unless their controller pays {2} for each creature they control that's attacking you.

Hanged Executioner

Flying
When Hanged Executioner enters, create a 1/1 white Spirit creature token with flying.
{3}{W}, Exile Hanged Executioner: Exile target creature.

Nebelgast Herald

Flash (You may cast this spell any time you could cast an instant.)
Flying
Whenever Nebelgast Herald or another Spirit you control enters, tap target creature an opponent controls.

Spectral Shepherd

Flying
{1}{U}: Return target Spirit you control to its owner's hand.

Island

Drogskol Reinforcements

Melee (Whenever this creature attacks, it gets +1/+1 until end of turn for each opponent you attacked this combat.)
Other Spirits you control have melee.
Prevent all noncombat damage that would be dealt to Spirits you control.

Sire of the Storm

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

Plains

Drogskol Captain

Flying
Other Spirit creatures you control get +1/+1 and have hexproof. (They can't be the targets of spells or abilities your opponents control.)