A ruler of this kingdom ordered all arrowheads fired towards his troops to be collected during a siege of Amsaka. This kingdom’s Duguwa dynasty came to power after subsuming the cities of the Sao civilization. A ruler of this kingdom legendarily opened a leather-bound mystical item called the mune, which Ibn Furtu equated to the Ark of the Covenant; that ruler was Dunama Dabbalemi. The rulers of Katsina were forced to send one hundred slaves to this kingdom’s capital at (*) Ngazargamu, whose ruins were (10[1])visited by Heinrich Barth in the 1800s. Hummay established this kingdom’s Sayfawa dynasty, (10[1])leading to the spread of Islam throughout this kingdom. This state’s mais, who were listed in the Girgam, included its greatest ruler Idris Alooma. (10[1])For 10 points, name this West African empire (-5[1])based around Lake Chad. ■END■ (10[1]0[1])