Mortal Coil is a free Warlock spell card that belongs to the "Legacy" set. The artist of this card was Matt Gaser, who also made 9 other artworks for Hearthstone.
The flavor text of the card is the following: If your spells look like horrifying skulls, let's be honest, you should get to draw some cards.
The card is easy to memorize with 99.1% of correct quiz questions.