Secrets of Arkham, the first deluxe expansion for Call of Cthulhu: The Card Game, opens a host of new deckbuilding opportunities for players looking to expand the horizons of their game. New "tribal" synergy deck options open up through additional support for the Deep One, Mi-Go, and other subtypes, as well as for the Day and Night mechanism. This set also introduces a wealth of utility neutral cards that will easily find their way into lots of different kinds of decks. Cards like "Diseased Sewer Rats" and "Feint" will become indispensable in the new metagame.

This set also features a new ten-card story deck that players can use in place of the story deck found in the Call of Cthulhu Core Set to take their game to a new level. These story cards will feature large, global effects, that players will fight hard to trigger...or prevent from happening.