Plains

Thriving Heath

This land enters tapped. As it enters, choose a color other than white.
{T}: Add {W} or one mana of the chosen color.

Starnheim Courser

Flying
Artifact and enchantment spells you cast cost {1} less to cast.

Sungrace Pegasus

Flying
Lifelink (Damage dealt by this creature also causes you to gain that much life.)

Pacifism

Enchant creature
Enchanted creature can't attack or block.

Aerial Assault

Destroy target tapped creature. You gain 1 life for each creature you control with flying.

Thurid, Mare of Destiny

Flying, lifelink
Whenever you cast a Pegasus, Unicorn, or Horse creature spell, copy it. (The copy becomes a token.)
Other Pegasi, Unicorns, and Horses you control get +1/+1.

Archon of Sun's Grace

Flying
Lifelink (Damage dealt by this creature also causes you to gain that much life.)
Pegasus creatures you control have lifelink.
Constellation — Whenever an enchantment you control enters, create a 2/2 white Pegasus creature token with flying.

Trusted Pegasus

Flying (This creature can't be blocked except by creatures with flying or reach.)
Whenever this creature attacks, target attacking creature without flying gains flying until end of turn.

Arborea Pegasus

Flying
When this creature enters, target creature gets +1/+1 and gains flying until end of turn.

Loyal Pegasus

Flying
This creature can't attack or block alone.

Pegasus Courser

Flying
Whenever this creature attacks, another target attacking creature gains flying until end of turn.

Phyrexian Pegasus

Flying
Whenever this creature attacks, another target attacking creature without flying gains flying until end of turn.

Banishing Light

When this enchantment enters, exile target nonland permanent an opponent controls until this enchantment leaves the battlefield.