2026-08-19 · history
Hakoiri Musume / Klotski (1930s) — The Lineage of Blocks That Trapped Cao Cao
In the West as a patent drawing, in China as a paper cutout re-enacting Cao Cao's defeat, and in Japan as a wooden toy called Hakoiri Musume — nearly the same sliding-block puzzle arose independently in three places between the 1890s and the 1930s, with no evidence any referenced the others. Martin Gardner published its 81-move optimal solution in Scientific American in 1964; Microsoft's Windows Entertainment Pack carried it to PCs worldwide in 1991. This is the record of that parallel evolution, up to 2021's Blockee on Steam, which names Klotski as its inspiration in its own words.
