Sakon Tigana, born 79 BBY, was a Jedi knight who became overwhelmed in hatred towards the Order and left it in the Clone Wars, as he had foreseen the Galactic Republic's downfall. After Order 66, he founded the Lighthunters, a brotherhood amassing the last survivors of the light side of the Force with an aim of standing in opposition to the overwhelming darkness.
In 17 ABY, together with the pupils of his, he headed to the planet of Alderaan to recapture Luminara Unduli, abducted by the Empire. Against the Hunters' favor, the history turned out fabricated, which resulted in Tigana himself being injured in the fight with the Grand Inquisitor and conveyed to Stygeon Prime.
In his presence in captivity, Tigana was freed by one amongst inquisitors, named Cos Dashit, who soon became another of his apprentices.
Sakon died in 16 ABY being tragically murdered by Darth Vader in his sleep upon the planet of Geonosis.
In the Jedi Order
Sakon Tigana was born in 79 BBY. He was the most likely to have been taken to the Jedi Order in his childhood to learn the ways of the Force.
Although Tigana received the rank of Jedi knight in an unspecific period prior to the battle of Geonosis, he was never appointed a master.
Leaving the Order
At an unspecified point of the Clone Wars, Tigana requested for being ruled out of the Jedi Order. This step was strenghtened with his lack of will to serve the organization which, according to him, engaged in the war in order to protect peace.
Directly before the Council's meeting whose judgement was positive from Tigana's view, Tigana had a talk with a temple guardian, who soon became Grand Inquisitor of the Galactic Empire.
In 21 ABY Sakon overtook to recruit the Force-sensitive to be his apprentices, which Taigon was the first among. He called them the Lighthunters and obligated himself to train them in the light side. After four years, every one of them could easily make use of a lightsaber. Their headquarter was located in a cave upon Geonosis, though Sakon himself resided in a house half a day away.
Sakon never showed his lightsaber to his apprentices, nor did he participate in missions and actions which they performed. He forbade them to show their faces for the Empire not to discover any details on them.
=Duel of Alderaan
In 17 ABY, along with every single one of his apprentices, Tigana headed to the planet of Alderaan. It was the first mission he had decided to engage in. In accordance with Senator Bail Organa's report, Luminara Unduli, a Jedi master found by him, was supposed to find herself in the Royal Mansion. Upon entering the chamber, Sakon began a talk to the planet's viceroy. The man sensed a far-reaching seriousness within his speaker. The conversation was interrupted by the Grand Inquisitor. Tigana ordered that his apprentices run away, and he himself stayed in fight with him. Although he originally had him pegged for Darth Vader, his identity was quickly recognized. The Pau'an explained to the Lighthunder that he was once a Jedi knight, and it was then that he referred to a talk they had ages before. He said that Sakon and he himself both betrayed the Republic and the very Order. Taking an advantage of his adversary's inattention, he stuck his lighsaber into his stomach, and then told the inquisitor called Dashit, coming into the room, to convey him to Styegon, upon which the Inquisitorius Base was located. Cos Dashit was supposed to account for the mission directly to the Emperor.
Out of captivity
Assuming you kill him, would it be in accordance to your values?
—Sakon Tigana, to Jacken Prime.
In his captivity, the injured Tigana was only healed in half. When, after the tortures, he did not confess any of the Order's secrets, he was decided to be transport to the AA34 cell. In that place, he had a conversation with his torturer, Dashit, who admitted not having killed any Jedi ever in his life. He also claimed to have joined the Inquisitorius in order to save his life. During the Clone Wars, Cos's master, in the character of Eath Koth, was said to have lost when on a certain mission. Left by the Council, the future inquisitor rose in hatred towards the Order, which Tigana also claimed to have endured.
Dashit offered his help to Sakon. By nightfall, they headed along a hallway. After Cos showed the former Jedi knight the futher way into the North Hangar, they were both unexpectedly attacked by three Lighthunters, including those named Governor and Jacen Prime. The elder man allowed the latter to get rid of Dashit, as well as he asked him if if would be in accordance with his personal values. As soon as the light side users let him go, they all four spotted two inquisitors on the other edge of the hall with their lightsaber ignited. One of the hunters pounced upon them, which cost him his life. When another of the enemies ran up, Jacken used the Force to push him aside.