Circle of Protection: Blue

{1}: The next time a blue source of your choice would deal damage to you this turn, prevent that damage.

Circle of Protection: Red

{1}: The next time a red source of your choice would deal damage to you this turn, prevent that damage.

Esper Sentinel

Whenever an opponent casts their first noncreature spell each turn, draw a card unless that player pays {X}, where X is Esper Sentinel's power.

Circle of Protection: Black

{1}: The next time a black source of your choice would deal damage to you this turn, prevent that damage.

Sigil of the Empty Throne

Whenever you cast an enchantment spell, create a 4/4 white Angel creature token with flying.

Circle of Protection: Green

{1}: The next time a green source of your choice would deal damage to you this turn, prevent that damage.

Plains

Endless Horizons

When Endless Horizons enters, search your library for any number of Plains cards, exile them, then shuffle.
At the beginning of your upkeep, you may put a card you own exiled with Endless Horizons into your hand.

Circle of Protection: White

{1}: The next time a white source of your choice would deal damage to you this turn, prevent that damage.

March of Otherworldly Light

As an additional cost to cast this spell, you may exile any number of white cards from your hand. This spell costs {2} less to cast for each card exiled this way.
Exile target artifact, creature, or enchantment with mana value X or less.

Disenchant

Luminarch Ascension

At the beginning of each opponent's end step, if you didn't lose life this turn, you may put a quest counter on Luminarch Ascension. (Damage causes loss of life.)
{1}{W}: Create a 4/4 white Angel creature token with flying. Activate only if Luminarch Ascension has four or more quest counters on it.