Four decks of cards for use with the Call of Cthulhu tabletop roleplaying game. Each deck provides the Keeper and players with handy references, information and notes. Contained within are: The Phobia Deck - 46 cards, each detailing the effects and consequences of a phobia, mania, or episode of madness. The Curious Characters Deck - 46 cards, each providing game characteristics and backstories for a range of characters that the players could meet during a game. The Unfortunate Events Deck - 46 cards, with all manner of strange, ill-fated and disastrous situations that will land the players in deep water. The Weapons and Artifacts Deck - 46 cards, each detailing a hand-to-hand, firearm or Mythos artifact. The Keeper can use these decks to supplement their scenarios: as inspiration when designing new encounters, to pass players secret and important notes during a game, and as a handy way to impart information. The different cards can enhance the story, advance the plot, as well as introduce friendly or villainous non-player characters.