Revenge of Ravens

Whenever a creature attacks you or a planeswalker you control, that creature's controller loses 1 life and you gain 1 life.

Sphere of Purity

If an artifact would deal damage to you, prevent 1 of that damage.

Valkmira, Protector's Shield

If a source an opponent controls would deal damage to you or a permanent you control, prevent 1 of that damage.
Whenever you or another permanent you control becomes the target of a spell or ability an opponent controls, counter that spell or ability unless its controller pays {1}.

Reidane, God of the Worthy

Flying, vigilance
Snow lands your opponents control enter the battlefield tapped.
Noncreature spells your opponents cast with mana value 4 or greater cost {2} more to cast.

Reidane, God of the Worthy // Valkmira, Protector's Shield

Battletide Alchemist

If a source would deal damage to a player, you may prevent X of that damage, where X is the number of Clerics you control.

Urza's Armor

If a source would deal damage to you, prevent 1 of that damage.

Vengeful Archon

Flying
{X}: Prevent the next X damage that would be dealt to you this turn. If damage is prevented this way, Vengeful Archon deals that much damage to target player or planeswalker.

Protection of the Hekma

If a source an opponent controls would deal damage to you, prevent 1 of that damage.

Bartolomé del Presidio

Sacrifice another creature or artifact: Put a +1/+1 counter on Bartolomé del Presidio.

Mephitic Draught

When Mephitic Draught enters the battlefield or is put into a graveyard from the battlefield, you draw a card and you lose 1 life.

Orbs of Warding

You have hexproof. (You can't be the target of spells or abilities your opponents control.)
If a creature would deal damage to you, prevent 1 of that damage.

Patron of the Kitsune

Fox offering (You may cast this card any time you could cast an instant by sacrificing a Fox and paying the difference in mana costs between this and the sacrificed Fox. Mana cost includes color.)
Whenever a creature attacks, you may gain 1 life.

Sphere of Grace

If a black source would deal damage to you, prevent 2 of that damage.

Guardian Seraph

Flying
If a source an opponent controls would deal damage to you, prevent 1 of that damage.

Arcane Signet

{T}: Add one mana of any color in your commander's color identity.

Thunderstaff

As long as Thunderstaff is untapped, if a creature would deal combat damage to you, prevent 1 of that damage.
{2}, {T}: Attacking creatures get +1/+0 until end of turn.

Sphere of Law

If a red source would deal damage to you, prevent 2 of that damage.

Comeuppance

Prevent all damage that would be dealt to you and planeswalkers you control this turn by sources you don't control. If damage from a creature source is prevented this way, Comeuppance deals that much damage to that creature. If damage from a noncreature source is prevented this way, Comeuppance deals that much damage to the source's controller.

Sphere of Truth

If a white source would deal damage to you, prevent 2 of that damage.

Inkshield

Prevent all combat damage that would be dealt to you this turn. For each 1 damage prevented this way, create a 2/1 white and black Inkling creature token with flying.

Sphere of Duty

If a green source would deal damage to you, prevent 2 of that damage.

Sol Ring

Ichor Wellspring

When Ichor Wellspring enters the battlefield or is put into a graveyard from the battlefield, draw a card.

Righteous Cause

Whenever a creature attacks, you gain 1 life.

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.)