During the war, in 1769 Lebian led a malón against the region of Laja River and Los Ángeles taking cattle and destroying every estancia in their path. Spanish troops sent against him were defeated and forced to retire to Los Ángeles. Encouraged by the victory Lebian attacked fort Santa Bárbara two days later, although repulsed with some losses, they managed to set fire to the town and to take the cattle found in the area.
At the end of the war he was part of the delegation sent to Santiago to make peace in 1774. The same year he was also involved in a feud against the toqui Ayllapagui.
In September 1776, according to Gov. Agustín de Jáuregui's policy of rewarding loyalty, Lebian was named distinguished soldier of the Spanish Army, and travelled to the city of Los Angeles for a meeting with the Maestro de CampoAmbrosio O'Higgins. As he was returning to his country, a band of Spaniards ambushed and killed him. One of the suspects was a captain Dionisio Contreras, but nothing was proved against him. It was rumored that O'Higgins had arranged the death as part of a policy of eliminating by such means hostile or strong Mapuche leaders in preference to open warfare, but O'Higgins denied responsibility for the ambush, persecuted the assassins and hanged one of them.