Astral Steel

Target creature gets +1/+2 until end of turn.
Storm (When you cast this spell, copy it for each spell cast before it this turn. You may choose new targets for the copies.)

Abeyance

Until end of turn, target player can't cast instant or sorcery spells, and that player can't activate abilities that aren't mana abilities.
Draw a card.

Lotus-Eye Mystics

Prowess (Whenever you cast a noncreature spell, this creature gets +1/+1 until end of turn.)
When Lotus-Eye Mystics enters, return target enchantment card from your graveyard to your hand.

Pearl Medallion

White spells you cast cost {1} less to cast.

Helm of Awakening

Monastery Mentor

Prowess (Whenever you cast a noncreature spell, this creature gets +1/+1 until end of turn.)
Whenever you cast a noncreature spell, create a 1/1 white Monk creature token with prowess.

Murmuration

Birds you control get +1/+1 and have vigilance.
At the beginning of your end step, for each spell you've cast this turn, create a 1/2 blue Bird creature token with flying named Storm Crow.

Angelsong

Prevent all combat damage that would be dealt this turn.
Cycling {2} ({2}, Discard this card: Draw a card.)

Adamant Will

Target creature gets +2/+2 and gains indestructible until end of turn. (Damage and effects that say "destroy" don't destroy it.)

Sphinx-Bone Wand

Whenever you cast an instant or sorcery spell, you may put a charge counter on Sphinx-Bone Wand. If you do, Sphinx-Bone Wand deals damage equal to the number of charge counters on it to any target.

Aetherflux Reservoir

Whenever you cast a spell, you gain 1 life for each spell you've cast this turn.
Pay 50 life: Aetherflux Reservoir deals 50 damage to any target.

Allay

Buyback {3} (You may pay an additional {3} as you cast this spell. If you do, put this card into your hand as it resolves.)
Destroy target enchantment.

Lapse of Certainty

Counter target spell. If that spell is countered this way, put it on top of its owner's library instead of into that player's graveyard.

Dragon Bell Monk

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

Apostle's Blessing

({W/P} can be paid with either {W} or 2 life.)
Target artifact or creature you control gains protection from artifacts or from the color of your choice until end of turn.

Jeskai Student

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

Eight-and-a-Half-Tails

{1}{W}: Target permanent you control gains protection from white until end of turn.
{1}: Target spell or permanent becomes white until end of turn.

Wing Shards

Target player sacrifices an attacking creature.
Storm (When you cast this spell, copy it for each spell cast before it this turn. You may choose new targets for the copies.)

Angelic Intervention

Target creature or planeswalker you control gains protection from colorless or from the color of your choice until end of turn. If it's a creature, put a +1/+1 counter on it. (It can't be blocked, targeted, dealt damage, enchanted, or equipped by anything with that quality.)

Acolyte's Reward

Prevent the next X damage that would be dealt to target creature this turn, where X is your devotion to white. If damage is prevented this way, Acolyte's Reward deals that much damage to any target. (Each {W} in the mana costs of permanents you control counts toward your devotion to white.)

Seeker of the Way

Prowess (Whenever you cast a noncreature spell, this creature gets +1/+1 until end of turn.)
Whenever you cast a noncreature spell, Seeker of the Way gains lifelink until end of turn.