The Search for Planet X

To set up the game, players first choose between standard mode (12 sectors) or expert mode (18 sectors). Each player then selects a difficulty level (novice, beginner, experienced, or genius), which determines the number of initial clues they receive. These clues are displayed on the companion app, which is essential for gameplay. Players also set up their individual player screens and note sheets, placing their pawns on the starting space of the time track. The game board, representing the solar system, is laid out, and the sun token is placed in the center.

The primary objective of 'The Search for Planet X' is to be the first player to correctly identify the sector where Planet X is located, as well as the two celestial objects in the sectors immediately adjacent to it. Alternatively, if no player successfully localizes Planet X before the game ends, the player with the most points from correctly published theories and other achievements will win. This requires careful deduction, strategic action selection, and efficient use of information gathered throughout the game.

Each turn consists of two main phases: performing an action and moving your pawn. First, players choose one of four actions: 'Search the Sky' allows players to check a range of sectors for a specific type of celestial object, costing time based on the size of the search area. 'Scan a Sector' lets players reveal the exact object in a single sector, also costing time. 'Conduct Research' enables players to gain logical rules about the distribution of celestial objects, costing one time unit. 'Hold a Conference' allows players to share a logical rule with all other players, costing one time unit. After performing an action, players move their pawn along the time track according to the cost of the chosen action, advancing towards the end of the game.

Points are awarded in several ways. The player who first correctly localizes Planet X receives 10 points. Other players who correctly localize Planet X in the same round receive points based on how far their pawn is from the first player's pawn on the time track (2-10 points). Players also earn points for publishing correct theories about the location or properties of celestial objects: asteroids give 2 points, comets 3 points, gas clouds 4 points, and dwarf planets 4 points (or 2 in expert mode). Additionally, 1 point is awarded for each sector where a player was the first to publish a correct theory.

The game concludes either immediately when a player successfully localizes Planet X, or when the time track reaches its final space, triggering a final scoring round. If Planet X is localized, the game ends, and points are tallied as described in the scoring section. If the game ends due to the time track, all players have one last chance to localize Planet X or publish theories before final scores are calculated. The player with the highest total score wins, combining points from Planet X localization, correct theories, and leadership bonuses.