Mysterium: Secrets & Lies includes six new characters, six new locations, six new items, and 18 story cards. This new group of cards can replace the object cards in the game, with each card representing a way the ghost died. Now instead of attempting to get each investigator to identify an object a singular item that wouldn't have much nuance to it the ghost instead must use the dream cards to convey the story of their demise, something much more challenging.