|Playing time||42 minutes|
|Age range||10 and up|
Mysterium is a cooperative board game designed by Oleksandr Nevskiy and Oleg Sidorenko. It blends aspects of murder mystery games and card-based guessing games. One person plays the ghost of a murdered individual who can communicate with the other players only through a series of visions in the form of illustrated cards. The other players, who take the role of psychic mediums, must interpret these cards to identify a suspect, location, and murder weapon. Following its release, Mysterium received positive reviews.
Thirty years ago, a servant was murdered in his employer’s mansion during a party. A group of mediums organize a séance to solve the mystery. The ultimate goal of the ghost is to indicate who killed him, where, and with what weapon. A series of illustrated cards are laid out for each of three stages: one for suspects, one for locations, and one for murder weapons. One person plays as the ghost. This player may not directly communicate with the other players, who play the mediums; however, the mediums may collaborate. The ghost secretly selects a suspect, location, and murder weapon for each medium to guess. Each round, the ghost hands out one or more illustrated cards to each medium, which is its sole means of communication with the players. Mediums progress through the stages by correctly guessing their respective suspect, location, and murder weapon. Players may indicate whether they believe guesses to be correct or not through tokens. If all players have advanced past the third stage by round seven, the ghost gives a final clue as to which medium holds the true identity of the ghost's murderer. Depending on how quickly players advanced through the stages and how many correct tokens they have placed, they may see one, two, or three cards from the ghost. Players may again collaborate on interpretation of the cards, but their final vote must be secret. If the majority guesses correctly, the players win and the ghost is set free to enjoy the afterlife.
Mysterium was initially published as Містеріум in Ukraine. French publisher Libellud, after acquiring the English- and French-language rights, made several changes to the rules and art.
Polygon identified it as one of the best games of Gen Con 2015. Nate Anderson of Ars Technica called it a "truly novel" combination of Dixit and Clue. Joshua Kosman of the San Francisco Chronicle rated it 5/5 stars and also compared it to Dixit and Clue. Matthew Baldwin of The Morning News compared it to Codenames, calling it more visual and complex. The game also won BoardGameGeek's 2015 Golden Geek Award for Best Artwork and Presentation.
- Anderson, Nate (2015-11-07). "Ars Cardboard: Mysterium's dreamy world is ghostly good fun". Ars Technica. Retrieved 2016-07-25.
- Hall, Charlie (2015-08-03). "Five of the best board games from Gen Con 2015". Polygon. Retrieved 2016-07-25.
- Kosman, Joshua (2015-12-02). "The best board games to play this year". San Francisco Chronicle. Retrieved 2016-07-25.
- Baldwin, Matthew (2015-12-07). "The 2015 Good Gift Games". The Morning News. Retrieved 2016-07-25.
- Hall, Charlie (2016-03-22). "The best board games of 2015, Board Game Geek's Golden Geek awards". Polygon. Retrieved 2016-07-25.