Kabal Courier is a rare Mage/Priest/Warlock minion card that belongs to the "Mean Streets of Gadgetzan" set, which was released on 01.12.2016 and is one of initially 132 cards. The artist of this card was Arthur Bozonnet, who also made 109 other artworks for Hearthstone.
The flavor text of the card is the following: Hey, you park your kodo under a harpy nest, you get what you deserve.
The card is easy to memorize with 100% of correct quiz questions.