consisted of a navy of heavy galleys each with 600–800 men, a cavalry using Persian horses, an elephant corps, conscripted infantry forces and more than 2000 cannons and guns (of both Sumatran and European origin). Upon gaining power, he began consolidating control over northern Sumatra. In 1612 he conquered Deli, and in 1613 Aru and Johor. Upon the conquest of Johor, its sultan, Alauddin Riayat Shah III, and other members of the royal family were brought to Aceh, along with a group of traders from the Dutch East India Company. However, Johor was able to expel the Acehnese garrison later that year, and Iskandar Muda was never able to assert permanent control over the area. Johor further built an alliance with Pahang, Palembang, Jambi, Inderagiri, Kampar and Siak against Aceh. Iskandar Muda's campaigns continued, however, and he was able to defeat a Portuguese fleet at Bintan in 1614. In 1617 he conquered Pahang and carried its sultan Ahmed Syah to Aceh, and thus achieved a foothold on the Malayan peninsula. This conquest was followed by Kedah in 1619, in which the capital was laid waste and the surviving inhabitants were brought to Aceh. A similar capture of Perak occurred in 1620, when 5,000 people were captured and left to die in Aceh. He again sacked Johor in 1623 and took Nias in 1624/5. At this point Aceh's strength seriously threatened the Portuguese holding of Melaka. In 1629, he sent several hundred ships to attack Melaka, but the mission was a devastating failure. According to Portuguese sources, all of his ships were destroyed along with 19,000 men. He however only managed to capture two major port cities in Melaka. After this loss, Iskandar Muda launched only two more sea expeditions, in 1630/1 and 1634, both to suppress revolts in Pahang and to firmly establish Islam in the region. His sultanate maintained control over northern Sumatra, but was never able to gain supremacy in the strait or expand the empire to the rich pepper-producing region of Lampung on the southern part of the island, which was under the control of the sultanate of Banten. Iskandar Muda was also known to be cruel as he devised torture techniques and caused humiliation to those who failed to please him. In one cockfighting match, a noble who won the match eventually suffered a humiliating death, while generals who failed in their exploits had been on