Oyumi were an ancient Japanese artillery piece that first appeared in the seventh century. It is unknown exactly what kind of weapon the Oyumi was or how it looked as there are no surviving examples or illustrations but the Oyumi is thought to have been a type of complicated crossbow.
According to Japanese records, the Oyumi was different from the hand held crossbow also in use during the same time period. This quote from a seventh-century source seems to suggest that the Oyumi may have able to fire multiple arrows at once "the Oyumi were lined up and fired at random, the arrows fell like rain". In the ninth century a Japanese artisan by the name of Shimaki no Fubito claimed that he had improved the Chinese version, and that his crossbow rotated so that it could fire stones or arrows in four directions. The last recorded use of the Oyumi was in 1189.