Shadow Essence is a rare Priest spell card that belongs to the "Knights of the Frozen Throne" set, which was released on 10.08.2017 and is one of initially 135 cards. The artist of this card was Matt Dixon, who also made 298 other artworks for Hearthstone.
The flavor text of the card is the following: Difficult to bottle up and sell. But it packs a punch.
The card is easy to memorize with 94.07% of correct quiz questions.
