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 .

Flying, vigilance

Snow lands your opponents control enter tapped.

Noncreature spells your opponents cast with mana value 4 or greater cost more to cast.