Remorseful Cleric

Flying
Sacrifice Remorseful Cleric: Exile target player's graveyard.

Spectral Sailor

Flash (You may cast this spell any time you could cast an instant.)
Flying
{3}{U}: Draw a card.

Supreme Phantom

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

Negate

Empyrean Eagle

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

Rattlechains

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

Temple of Enlightenment

Temple of Enlightenment enters tapped.
When Temple of Enlightenment enters, scry 1.
{T}: Add {W} or {U}.

Geist of Saint Traft

Hexproof (This creature can't be the target of spells or abilities your opponents control.)
Whenever Geist of Saint Traft attacks, create a 4/4 white Angel creature token with flying that's tapped and attacking. Exile that token at end of combat.

Shacklegeist

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

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.)

Glacial Fortress

Glacial Fortress enters tapped unless you control a Plains or an Island.
{T}: Add {W} or {U}.

Watcher of the Spheres

Flying
Creature spells with flying you cast cost {1} less to cast.
Whenever another creature you control with flying enters, Watcher of the Spheres gets +1/+1 until end of turn.

Snow-Covered Island

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.

Snow-Covered Plains

Lofty Denial

Counter target spell unless its controller pays {1}. If you control a creature with flying, counter that spell unless its controller pays {4} instead.

Spell Queller

Flash
Flying
When Spell Queller enters, exile target spell with mana value 4 or less.
When Spell Queller leaves the battlefield, the exiled card's owner may cast that card without paying its mana cost.