Urza's Armor

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

Plated Pegasus

Flash (You may cast this spell any time you could cast an instant.)
Flying
If a spell would deal damage to a permanent or player, prevent 1 damage that spell would deal to that permanent or player.

Guardian Seraph

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

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.

Protection of the Hekma

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

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.

Pariah

Enchant creature
All damage that would be dealt to you is dealt to enchanted creature instead.

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

Hedron-Field Purists

Level up {2}{W} ({2}{W}: Put a level counter on this. Level up only as a sorcery.)
LEVEL 1-4
1/4
If a source would deal damage to you or a creature you control, prevent 1 of that damage.
LEVEL 5+
2/5
If a source would deal damage to you or a creature you control, prevent 2 of that damage.