Sephara, Sky's Blade

You may pay {W} and tap four untapped creatures you control with flying rather than pay this spell's mana cost.
Flying, lifelink
Other creatures you control with flying have indestructible. (Damage and effects that say "destroy" don't destroy them.)

Spectral Procession

Create three 1/1 white Spirit creature tokens with flying.

Path to Exile

Exile target creature. Its controller may search their library for a basic land card, put that card onto the battlefield tapped, then shuffle.

Tranquil Cove

This land enters tapped.
When this land enters, you gain 1 life.
{T}: Add {W} or {U}.

Island

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.

Mausoleum Wanderer

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

Hour of Reckoning

Convoke (Your creatures can help cast this spell. Each creature you tap while casting this spell pays for {1} or one mana of that creature's color.)
Destroy all nontoken creatures.

Lingering Souls

Create two 1/1 white Spirit creature tokens with flying.
Flashback {1}{B} (You may cast this card from your graveyard for its flashback cost. Then exile it.)

Selfless Spirit

Flying
Sacrifice this creature: Creatures you control gain indestructible until end of turn.

Plains

Temple of Enlightenment

This land enters tapped.
When this land enters, scry 1. (Look at the top card of your library. You may put that card on the bottom.)
{T}: Add {W} or {U}.

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.)

Favorable Winds

Creatures you control with flying get +1/+1.

Mana Leak

Counter target spell unless its controller pays {3}.

Seachrome Coast

This land enters tapped unless you control two or fewer other lands.
{T}: Add {W} or {U}.

Smuggler's Copter

Flying
Whenever this Vehicle attacks or blocks, you may draw a card. If you do, discard a card.
Crew 1 (Tap any number of creatures you control with total power 1 or more: This Vehicle becomes an artifact creature until end of turn.)