Shō shōgi (小将棋 'small chess') is a 16th-century form of shogi (Japanese chess), and the immediate predecessor of the modern game. It was played on a 9×9 board with the same setup as in modern shogi, except that an extra piece stood in front of the king: a 'drunk elephant' that promoted into a prince, which is effectively a second king. While 9×9 may not seem 'small', it was smaller than the other shogi variants prevalent at the time, which were the 12×12 chu shogi and 15×15 dai shogi. According to the Sho Shōgi Zushiki, the drunk elephant was eliminated by the Emperor Go-Nara[1] (reigned 1526–1557), and it is assumed that the drop rule was introduced at about the same time, giving rise to shogi as we know it today.