Roaming Ghostlight

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

Battleground Geist

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

Tome Anima

Tome Anima can't be blocked as long as you've drawn two or more cards this turn.

Murmuring Phantasm

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.

Befuddle

Target creature gets -4/-0 until end of turn.
Draw a card.

Island

Thriving Isle

Thriving Isle enters the battlefield tapped.
As Thriving Isle enters the battlefield, choose a color other than blue.
{T}: Add {U} or one mana of the chosen color.

Departed Deckhand

When Departed Deckhand becomes the target of a spell, sacrifice it.
Departed Deckhand can't be blocked except by Spirits.
{3}{U}: Another target creature you control can't be blocked this turn except by Spirits.

Winged Words

This spell costs {1} less to cast if you control a creature with flying.
Draw two cards.

Shacklegeist

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

Frost Breath

Tap up to two target creatures. Those creatures don't untap during their controller's next untap step.

Capture Sphere

Flash (You may cast this spell any time you could cast an instant.)
Enchant creature
When Capture Sphere enters the battlefield, tap enchanted creature.
Enchanted creature doesn't untap during its controller's untap step.

Essence Flux

Exile target creature you control, then return that card to the battlefield under its owner's control. If it's a Spirit, put a +1/+1 counter on it.