Pure Intentions

Whenever a spell or ability an opponent controls causes you to discard cards this turn, return those cards from your graveyard to your hand.
When a spell or ability an opponent controls causes you to discard Pure Intentions, return Pure Intentions from your graveyard to your hand at the beginning of the next end step.

Hundred-Talon Strike

Target creature gets +1/+0 and gains first strike until end of turn.
Splice onto Arcane—Tap an untapped white creature you control. (As you cast an Arcane spell, you may reveal this card from your hand and pay its splice cost. If you do, add this card's effects to that spell.)

Charge Across the Araba

Sweep — Return any number of Plains you control to their owner's hand. Creatures you control get +1/+1 until end of turn for each Plains returned this way.

Shining Shoal

You may exile a white card with mana value X from your hand rather than pay this spell's mana cost.
The next X damage that a source of your choice would deal to you and/or creatures you control this turn is dealt to any target instead.

Otherworldly Journey

Exile target creature. At the beginning of the next end step, return that card to the battlefield under its owner's control with a +1/+1 counter on it.

Blessed Breath

Target creature you control gains protection from the color of your choice until end of turn.
Splice onto Arcane {W} (As you cast an Arcane spell, you may reveal this card from your hand and pay its splice cost. If you do, add this card's effects to that spell.)

Cleanfall

Clarion Spirit

Whenever you cast your second spell each turn, create a 1/1 white Spirit creature token with flying.

Terashi's Grasp

Destroy target artifact or enchantment. You gain life equal to its mana value.

Ethereal Haze

Prevent all damage that would be dealt by creatures this turn.

Quiet Purity

Plow Through Reito

Sweep — Return any number of Plains you control to their owner's hand. Target creature gets +1/+1 until end of turn for each Plains returned this way.

Celestial Kirin

Flying
Whenever you cast a Spirit or Arcane spell, destroy all permanents with that spell's mana value.