History of Opaque Card

An Opaque Card is an unrevealed Whisper Card from Season of the Witch, part of the Deck of Whispers (55 cards: 12 Major and 43 Minor Arcana).

Acquisition

Seasonal story quests, Major Arcana quests, Ritual Table ranks, collectibles and drops from Savathûn's Spire and Altars of Summoning.

Use

Reveal them at the Lectern of Divination in the Athenaeum. A deck needs five Major Arcana to start and a card is drawn each combat encounter in the Spire and Altars (The Gamer).