The Battle of Iskalon represents the second significant engagement during the Nagai's invasion, occurring in 4 ABY.
Following the events of the Second Battle of Endor, Luke Skywalker and Lando Calrissian journeyed to Iskalon. Their objective was to inform the Iskalonian population about the demise of Kiro, who was killed by Den Siva on Kinooine. Upon landing at the devastated city of Pavillion, the pair discovered the small platform was covered with the dead bodies of Nagai warriors. These Nagai, commanded by General Kruskob Tiltanka, had invaded the planet and taken the School captive, employing lethal sonic blasters. The Nagai slaughtered a number of Iskalonians when they refused to construct the Nagai base.
After a discussion with Mone, the Iskalonian leader, Luke and Lando came to understand that Kiro was, surprisingly, still alive. Having escaped Siva on Kinooine, Kiro had returned to Iskalon and began resisting the Nagai's construction efforts on the world. After the prisoners had been killed, he launched a counterattack, leaving the platform littered with Nagai corpses for Luke to discover. When Skywalker, Calrissian, and Mone were attacked by a Nagai squad, Kiro revealed himself. While he managed to shield Luke and Lando, Kiro couldn't prevent Mone, Dania Francis, and their school of Iskalonians from being captured by the Nagai. Kiro departed from the scene swiftly, preventing Luke from speaking with his longtime friend.
With Pavilion secured, Luke and Lando put on rebreathers and went underwater, with the intention of destroying the Nagai's tower. Luke gave Lando his shoto, and they started demolishing the structure using Luke's two lightsabers, but they were ambushed by a Nagai patrol. Kiro appeared once more, defeating the Nagai soldiers. Kiro then went inside the tower in an attempt to rescue Mone and the captured Iskalonians, who the Nagai were using as slaves. Luke followed him, leaving Lando to destroy the tower's foundation.
Even though Luke and Kiro succeeded in freeing Mone and the others, a Nagai shot Kiro in the heart, seemingly killing him. Lando caused the tower to collapse into the sea, ending the Nagai's control over the planet. Kiro then revealed himself to Luke – he had not actually been killed, but had faked his death a second time. He requested Luke to keep his survival a secret, especially from the Zeltron Dani, before vanishing into the waters for good.