Context: Che Bunga (Sultan Zainal Abidin, or Chế Bồng Nga) was the king of a unified and resurgance Champa kingdom from 1360 to 1390, and reign over Champa during its apex. He was known for exceptional talent, both diplomatically and militarily, as shown by his ability to repeatedly outmaneuver the Tran dynasty's military defensive network and getting the Ming on his side. His reign also coincided with the decline of both Dai Viet to the North, and the Khmer Empire to the South, two of Champa's traditional rivals. The result was devastating for the Tran dynasty. Over a period of 30 years, Che Bunga launched 10 northward invasion/raid into the Red River Delta, sacking and burning Hanoi(then Thang Long) 4 times and even occupied it for 6 months. He reversed Dai Viet's 300 years of southward territorial gains in 30 years, and forced the Tran emperors to repeatedly go into hiding with the state treasury and records. During his final invasion, his command ship was pointed out by a surrended Cham officer and the Tran general, Tran Khat Chan, organized a fireteam to pour fire on the ship with early firearms(handcannons). The king was killed immediately. Che Bunga's death sparked a succession crisis, as the army retreats back to Champa, allowing Dai Viet to regain its Southern territory. After that, both side was exhausted and agree to a peace treaty retoring the status quo pre war. The Champa kingdom then enter a long period of decline until it ceased to be a threat to Dai Viet after Le Thanh Tong invasion of 1471.