You play Pacru on a board consisting of a grid of nine tiles by nine tiles, divided into nine "borderlands". The game centers on the interaction between pieces (four each) and tiles. The board starts with neutral tiles in each position and as the game progresses you replace the tiles with your own color by moving across borders. As you gain more tiles in a borderland, so your pieces there gain more power of movement. Using a connection change you can sweep a piece across the board changing tiles to your color, or with two pieces you can pincer an opposition piece. You win the game by placing your 42nd tile on the board, or by eliminating all your the opponent's pieces. You will probably take 15 minutes from first acquaintance to grasping the rules.
With 3 or 4 players you start with 3 pieces each.
Separate entries exist for Pacru, Shacru & Azacru as opinions vary widely on the 3 games.