Sources are extremely thin, and most piece movements are only guessed at. This implementation is a speculative reconstruction built from the surviving fragmentary descriptions.
王 King — moves to an adjacent empty square only (cannot capture)学 Scientist — 1 diagonal square only砲 Rocket — slides like a rook, but captures by jumping exactly one piece馬 Knight — ordinary knight兵 Pawn — 1 square only
"Semedo" is said to be named for Álvaro Semedo, a Jesuit missionary in 17th-century China. The only surviving description of this shogi-like game appears in a 1694 English publication by Thomas Hyde, and it's so sparse that some historians doubt the game existed in the form described at all. The few features that do survive: the king cannot attack (it may move but not capture, or perhaps cannot move at all), a "Rocket" piece reminiscent of the cannon in Xiangqi (captures by jumping exactly one piece), and a "Scientist" advisor-type piece.
Speculative reconstruction: since exact piece movements and board size aren't recorded, this blends Xiangqi-style pieces (the Rocket and Scientist) with Western ones (Knight, Pawn) into an original best guess. The king may only move to an adjacent empty square and can never capture (interpreting the "cannot attack" note). Check and checkmate aren't enforced — capturing the king directly ends the game.