In Codex Naturalis you must continue the work of the insightful monk Tybor Kwelein and compile the pages of a manuscript listing the living species. Can you put the pages together in the best possible order? And are you willing to sacrifice a species to develop your manuscript?

In the game, each player starts with a single card on the table, a card that is a combination of the four possible resources. During a turn, you place a card from your hand whose corners overlap with one or more cards you already have in play. Your starting card has four overlapping corners, while resource and gold cards only have three.

If you wish, you can play a card from your hand face down; such a card has four corners and one resource, but does not score any points. After playing, draw a face-up card or the top card from one of the piles to complete your hand.

When a player reaches 20 points, you complete the round and each player takes an extra turn. Players then score points based on how well they match two public objective cards and one secret objective card, with the player with the most points winning.