Prismatic Strands

Prevent all damage that sources of the color of your choice would deal this turn.
Flashback—Tap an untapped white creature you control. (You may cast this card from your graveyard for its flashback cost. Then exile it.)

Guardians' Pledge

White creatures you control get +2/+2 until end of turn.

Charge

Creatures you control get +1/+1 until end of turn.

Gather the Townsfolk

Create two 1/1 white Human creature tokens.
Fateful hour — If you have 5 or less life, create five of those tokens instead.

Battle Screech

Create two 1/1 white Bird creature tokens with flying.
Flashback—Tap three untapped white creatures you control. (You may cast this card from your graveyard for its flashback cost. Then exile it.)

Soul's Attendant

Whenever another creature enters, you may gain 1 life.

Soul Warden

Whenever another creature enters, you gain 1 life.

Raise the Alarm

Create two 1/1 white Soldier creature tokens.

Thraben Inspector

When Thraben Inspector enters, investigate. (Create a Clue token. It's an artifact with "{2}, Sacrifice this artifact: Draw a card.")

Veteran Armorer

Triplicate Spirits

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

Squadron Hawk

Flying
When Squadron Hawk enters, you may search your library for up to three cards named Squadron Hawk, reveal them, put them into your hand, then shuffle.