Nykthos, Shrine to Nyx

{T}: Add {C}.
{2}, {T}: Choose a color. Add an amount of mana of that color equal to your devotion to that color. (Your devotion to a color is the number of mana symbols of that color in the mana costs of permanents you control.)

Banisher Priest

When Banisher Priest enters, exile target creature an opponent controls until Banisher Priest leaves the battlefield. (That creature returns under its owner's control.)

Keening Apparition

Sacrifice Keening Apparition: Destroy target enchantment.

Judge's Familiar

Flying
Sacrifice Judge's Familiar: Counter target instant or sorcery spell unless its controller pays {1}.

Loyal Pegasus

Flying
Loyal Pegasus can't attack or block alone.

Brave the Elements

Choose a color. White creatures you control gain protection from the chosen color until end of turn.

Soldier of the Pantheon

Protection from multicolored
Whenever an opponent casts a multicolored spell, you gain 1 life.

Boros Elite

Battalion — Whenever Boros Elite and at least two other creatures attack, Boros Elite gets +2/+2 until end of turn.

Azorius Arrester

When Azorius Arrester enters, detain target creature an opponent controls. (Until your next turn, that creature can't attack or block and its activated abilities can't be activated.)

Plains

Daring Skyjek

Battalion — Whenever Daring Skyjek and at least two other creatures attack, Daring Skyjek gains flying until end of turn.

Imposing Sovereign

Creatures your opponents control enter tapped.

Dryad Militant

If an instant or sorcery card would be put into a graveyard from anywhere, exile it instead.