
Sanctifier of Souls | Creature | Human Cleric | Whenever another creature enters the battlefield under your control, Sanctifier of Souls gets +1/+1 until end of turn.
{2}{W}, Exile a creature card from your graveyard: Create a 1/1 white Spirit creature token with flying. | Jesper Ejsing

Identity Thief | Creature | Shapeshifter | Whenever Identity Thief attacks, you may exile another target nontoken creature. If you do, Identity Thief becomes a copy of that creature until end of turn. Return the exiled card to the battlefield under its owner's control at the beginning of the next end step. | Magali Villeneuve

Niblis of Frost | Creature | Spirit | Flying
Prowess (Whenever you cast a noncreature spell, this creature gets +1/+1 until end of turn.)
Whenever you cast an instant or sorcery spell, tap target creature an opponent controls. That creature doesn't untap during its controller's next untap step. | Josu Hernaiz

Impetuous Devils | Creature | Devil | Trample, haste
When Impetuous Devils attacks, up to one target creature defending player controls blocks it this combat if able.
At the beginning of the end step, sacrifice Impetuous Devils. | Filip Burburan

Heron's Grace Champion | Creature | Human Knight | Flash
Lifelink
When Heron's Grace Champion enters the battlefield, other Humans you control get +1/+1 and gain lifelink until end of turn. | Todd Lockwood

Bloodhall Priest | Creature | Vampire Cleric | Whenever Bloodhall Priest enters the battlefield or attacks, if you have no cards in hand, Bloodhall Priest deals 2 damage to any target.
Madness {1}{B}{R} (If you discard this card, discard it into exile. When you do, cast it for its madness cost or put it into your graveyard.) | Mark Winters