Portal Chess starting location of these portals can be different when the game begins, but the image shows the standard set-up. In this game the portal pieces move around by very specific rules. This version of the game has "player-controlled portals", which are linked to each other. The rules for these portals are worked out as though they make the squares they cover into one square. In the set up to the right, a5 and e4 can be conceptualized as the same square. The specific rules for portal use are as follows: Portal Chess Portal Chess is a chess variant which uses
Chess and is provably less than 10, with a game-tree complexity of approximately 10. The game-tree complexity of chess was first calculated by Claude Shannon as 10, a number known as the Shannon number. Typically an average position has thirty to forty possible moves, but there may be as few as zero (in the case of checkmate or stalemate) or (in a constructed position) as many as 218. Chess has inspired many combinatorial puzzles, such as the knight's tour and the eight queens puzzle. The idea of creating a chess-playing machine dates to the 18th century; around 1769, the chess-playing automaton