In Ancient Egypt, more than three millenia ago, men confronted each other in the Trial of Osirium under the eyes of the immortal Gods. Inspired by Osiris, the judge of souls who came back from the dead, the Osirium allowed to settle many conficts and to have the truth triumph. If honesty guides your actions, then you won’t be afraid of walking in the duat, and you will make your Deity proud.

Goal of the Game
Osirium is a trial. Your goal is to defeat your opponents to make the deity to whom you pledged allegiance proud. To do that, you need to collect as many points (or Ankhs) as possible, performing Rituals with various Amulets. 4 deities are available: Isis, Anubis, Bastet and Seth.
The Trial
The oldest player plays first, since it is assumed that they’ll join the gods sooner than the others… Then, the player on their left plays their turn, and so on.

On your turn,

You must play one of your 4 Amulet Cards. Place it on any free space of the board, choosing its orientation. Then, draw a new Amulet Card to have 4 Amulet Cards in your hand again. You can either take an Amulet Card from the Deities’ Market, or draw a random Amulet Card from the top of the draw pile. If you take a card from the Market, immediately replace it with a new card from the draw pile.
You may cast one of the Rituals of your Deity Board (see Cast a Ritual on p.7). You can do this before or after placing an Amulet on the board. You can cast as many Rituals as you like. Casting a Ritual is not mandatory.

Alternatively, you may decide to pass. This allows you to discard your entire hand of Amulet Cards to draw 4 new Amulet Cards instead. When you pass, ignore the two actions listed above.
The Trial ends once a player has cast 5 Rituals. Check if any player has completed their Exaltation Card (a secret secondary objective), then proceed to final scoring.

Cast a Ritual
There are two types of Rituals: Simple Rituals and Advanced Rituals. Players receive Simple Rituals at the beginning of the game. They are easy to cast but do not score many points. Players may draw Advanced Rituals during the game. These Rituals score more points. Each Ritual Card depicts the Amulets required to cast the Ritual.
To cast a Ritual, you must make sure that the depicted Amulets are correctly linked to each other: An Amulet is linked to the adjacent Amulet if both arrows are face to face. There must be no other Amulets between the arrows of the Amulets required to cast the Ritual. There can be more Amulets than required, of course. In that case, simply indicate the ones that you are using.
A Ritual allows you to gain Ankhs (as many as indicated on the card, in front of the matching symbol). However, casting a Ritual consumes the Amulets’ energy. For this reason, some of them need to be broken. Remove the Amulet(s) of your choice from the ones used for the Ritual and place them in front of you.
Rituals can be cast according to two principles: Order OR Chaos.
ORDER : Such Rituals score more points and break less Amulets – which means that more Amulets remain available for the other players.
CHAOS : The black symbols depict the Chaos Principle. Such Rituals score less points and break more Amulets.

—description from the publisher

Run Animals, Run!