The sai was originally an agricultural tool, but then became an Improvised Weapon often associated with Ninja. In real life, sai are very rarely actually bladed weapons, and are primarily used in defense in order to disarm and/or break blades. In fiction, however, the middle prong (or both) is usually sharpened into a makeshift dagger. (Sometimes Truth in Television, but not normal practice.) Unusually, Dual-Wielding a pair of sais is Truth in Television. The Other Wiki has more details on the historical use of the sai here. Examples of Sai Guy include: