Mendelius is a card game for which one or more Mendelius decks are needed (a deck for every two players). The goal is to be the first player to make different combinations of cards, or crossings. Mendelius is an educational game that presents the genetic basis of the Mendelian inheritance. A game of Mendelius is played in seven rounds. In each round you have to perform several predetermined crossingss whose difficulty increases as the game progresses, as in other card games such as Gin Rummy. The winner of the round discounts 10 points, while the other players are assigned a score corresponding to the sum of the value of the cards that have been left in their hands at the end of the round. The winner is the player with the lowest score at the end of the game.