The Massassi were an ancient primitive warrior race that were enslaved by the Sith. The Massassi were brought to Yavin 4 by the Sith Lord Naga Sadow who was on the run from the Republic and the Jedi. They were originally a red-skinned humanoid race until Naga Sadow conducted cruel genetic experiments on them turning them into a race of fearsome, savage, hunchbacked predators. Despite this cruelty, the Massassi treated Naga Sadow as a god by building huge temples and palaces to honor their Sith Lord. They became extinct when Exar Kun sapped the life out of every Massassi on Yavin 4 so that he could free his soul from his body in order to escape the pursuing Jedi. Only one Massassi, named Kalgrath, survived.
During the Galactic Civil War, the Rebel Alliance built a base in the old Massassi temples on Yavin 4. It was from this hidden base that Rebel starships were able to score their first victory against the Empire, and from which squadrons of X-wings and Y-wings attacked and destroyed the first Death Star.
In 22 ABY, during the time covered by the Junior Jedi Knights Series, Anakin Solo and Tahiri Veila were led by the Force to find a large golden globe deep inside a Massassi temple on Yavin 4. Inside the globe were the imprisoned souls of Massassi children whom the young Jedi candidates eventually freed with guidance from Jedi Master Ikrit.
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