Game description from the publisher:
Into Tartarus explores the kernel of truth at the root of every myth with 60 new cards (three copies each of 20 unique cards) for Call of Cthulhu: The Card Game. The fifth Asylum Pack in the "Ancient Relics" cycle, Into Tartarus transports archaeologists, investigators, cultists, and criminals to Greece where each faction uncovers new chaos while searching ancient ruins for powerful relics.
Several of the cards from Into Tartarus enable players to stir up all new manners of chaos. Agency decks gain cards to work against the chaos, while Cthulhu and Shub-Niggurath decks gain terrifying new attachments. Several factions gain powerful new Relics, further expanding deck-building options centered around these strange and powerful items.