Mindshrieker

Flying
{2}: Target player mills a card. Mindshrieker gets +X/+X until end of turn, where X is the milled card's mana value.

Latch Seeker

Ascendant Spirit

{S}{S}: Ascendant Spirit becomes a Spirit Warrior with base power and toughness 2/3.
{S}{S}{S}: If Ascendant Spirit is a Warrior, put a flying counter on it and it becomes a Spirit Warrior Angel with base power and toughness 4/4.
{S}{S}{S}{S}: If Ascendant Spirit is an Angel, put two +1/+1 counters on it and it gains "Whenever this creature deals combat damage to a player, draw a card."

Stormbound Geist

Flying
Stormbound Geist can block only creatures with flying.
Undying (When this creature dies, if it had no +1/+1 counters on it, return it to the battlefield under its owner's control with a +1/+1 counter on it.)

Roaming Ghostlight

Flying
When Roaming Ghostlight enters the battlefield, return up to one target non-Spirit creature to its owner's hand.

Dungeon Geists

Flying
When Dungeon Geists enters the battlefield, tap target creature an opponent controls. That creature doesn't untap during its controller's untap step for as long as you control Dungeon Geists.

Geist of the Lonely Vigil

Defender, flying
Delirium — Geist of the Lonely Vigil can attack as though it didn't have defender as long as there are four or more card types among cards in your graveyard.

Usher of the Fallen

Boast — {1}{W}: Create a 1/1 white Human Warrior creature token. (Activate only if this creature attacked this turn and only once each turn.)

Unimpeded Trespasser

Uninvited Geist

Skulk (This creature can't be blocked by creatures with greater power.)
When Uninvited Geist deals combat damage to a player, transform it.

Uninvited Geist // Unimpeded Trespasser

Battleground Geist

Flying
Other Spirit creatures you control get +1/+0.

Drogskol Reaver

Flying, double strike, lifelink
Whenever you gain life, draw a card.

Empyrean Eagle

Flying
Other creatures you control with flying get +1/+1.

Nebelgast Herald

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

Rattlechains

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

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.

Tradewind Rider

Flying
{T}, Tap two untapped creatures you control: Return target permanent to its owner's hand.

Niblis of Dusk

Flying
Prowess (Whenever you cast a noncreature spell, this creature gets +1/+1 until end of turn.)

Tower Geist

Flying
When Tower Geist enters the battlefield, look at the top two cards of your library. Put one of them into your hand and the other into your graveyard.

Shacklegeist

Flying
Shacklegeist can block only creatures with flying.
Tap two untapped Spirits you control: Tap target creature you don't control.

Chameleon Spirit

As Chameleon Spirit enters the battlefield, choose a color.
Chameleon Spirit's power and toughness are each equal to the number of permanents of the chosen color your opponents control.

Niblis of the Breath

Flying
{U}, {T}: You may tap or untap target creature.

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.)

Skyclave Apparition

When Skyclave Apparition enters the battlefield, exile up to one target nonland, nontoken permanent you don't control with mana value 4 or less.
When Skyclave Apparition leaves the battlefield, the exiled card's owner creates an X/X blue Illusion creature token, where X is the mana value of the exiled card.

Ghastly Haunting

Enchant creature
You control enchanted creature.

Soul Seizer

Flying
When Soul Seizer deals combat damage to a player, you may transform it. If you do, attach it to target creature that player controls.

Soul Seizer // Ghastly Haunting

Clarion Spirit

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

Fogwalker

Skulk (This creature can't be blocked by creatures with greater power.)
When Fogwalker enters the battlefield, target creature an opponent controls doesn't untap during its controller's next untap step.

Erdwal Illuminator

Flying
Whenever you investigate for the first time each turn, investigate an additional time.

Geist of the Archives

Defender
At the beginning of your upkeep, scry 1. (Look at the top card of your library. You may put that card on the bottom of your library.)

Sturmgeist

Flying
Sturmgeist's power and toughness are each equal to the number of cards in your hand.
Whenever Sturmgeist deals combat damage to a player, draw a card.

Niblis of Frost

Flying
Prowess (Whenever you cast a noncreature spell, this creature gets +1/+1 until end of turn.)
Whenever you cast an instant or sorcery spell, tap target creature an opponent controls. That creature doesn't untap during its controller's next untap step.

Windborn Muse

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

Supreme Phantom

Flying
Other Spirits you control get +1/+1.

Deadeye Navigator

Soulbond (You may pair this creature with another unpaired creature when either enters the battlefield. They remain paired for as long as you control both of them.)
As long as Deadeye Navigator is paired with another creature, each of those creatures has "{1}{U}: Exile this creature, then return it to the battlefield under your control."