Ritual of Doom is a Warlock spell card (rarity: rare) that belongs to the "Legacy" set. The artist of this card was L. Lullabi & A. Bozonnet, who also made 5 other artworks for Hearthstone.
The card costs 0 mana and its card text reads: "Destroy a friendly minion. If you had 5 or more, summon a 5/5 Demon."
The flavor text of the card is the following: "Who wants to sing the Doom song?!"
Based on 56 quiz answers, the card is moderately hard to memorize: 86% of them were correct. The question on “Name” is answered correctly most often (95%), the one on “Cost” least often (73%). An answer takes 9.1 seconds on average. In the Pixel Quiz, which shows only the shape and colour of the card, it was recognised correctly 83% of the time.