of the Three Kingdoms" is played on a special hexagonal board with three xiangqi armies (red, blue, and green) vying for dominance. A Y-shaped river divides the board into three gem-shaped territories, each containing the grid found on one side of a xiangqi board, but distorted to make the game playable by three people. Each player has eighteen pieces: the sixteen of regular xiangqi, plus two new ones that stand on the same rank as the cannons. The new pieces have different names depending on their side: huo ("fire") for Red, qi ("flag") for Blue, and feng ("wind") for Green. They move two spaces orthogonally, then one space diagonally. The generals each bear the name of a historical Chinese kingdom—Shu for Red, Wei for Blue, and Wu for Green—from China's Three Kingdoms period. It is likely that San Guo Qi first appeared under the Southern Song dynasty (1127–1279). San You Qi "Three Friends Chess" was invented by Zheng Jinde from Shexian in the Anhui province during the reign of the Kangxi Emperor of the Qing dynasty (1661–1722). It is played on a Y-shaped board with a full army of xiangqi pieces set up at the end of each of the board's three wide radii. In the centre of the board sits a triangular zone with certain features, such as ocean, mountain, or city walls, each of which is impassable by certain pieces. Two of an army's five soldiers are replaced by new pieces called huo ("fire") pieces, which move one space diagonally forward. Two qi ("flag") pieces are positioned on the front corners of the palace; they move two spaces forward inside their own camp, and then one space in any direction inside an enemy camp. Sanrenqi "Three Men Chess" is a riverless, commercial variant played on a cross-shaped board with some special rules, including a fourth, neutral country called Han. Han has three Chariots, one Cannon, and one General named "Emperor Xian of Han", but these pieces do not move and do not belong to any of the players until a certain point in the game when two players team up against the third player. At that point the third player gets to also control Han. Si Guo Qi "Four Kingdoms Chess" is also played on a riverless, cross-shaped board, but with four players. Because there are no rivers, elephants may move about the board freely. Qi Guo Xiang