- "Ancient warriors built the Great Temple more than 5,000 years ago."
- ―Tour the Great Temple on Yavin 4
The Massassi were a species who lived on Yavin 4, the fourth moon of Yavin Prime. Thousands of years before the Imperial Era, they built enormous stone temples on the moon for unknown purposes. It was believed that the Massassi may have been a slave race in thrall to the Sith, who brought them to the moon. The Massassi went extinct sometime after finishing their temples.
The Massassi were a mysterious species that built enormous stone temples of unknown purpose on the fourth moon of Yavin some five thousand years before the rise of the Galactic Empire. Whether the Massassi had evolved on Yavin 4 or were a slave race in thrall of the Sith and brought to that moon was unknown, although the latter seemed more likely. Sometime after finishing their temples, however, they went extinct. At some point, either as part of the original intent of the building or through ulterior additions, the Jedi splinter group known as the Ordu Aspectu used one of the Massassi temples, the Great Temple, to store information, including a map room that gave directions to their hidden headquarters.
After their extinction, the Massassi were mentioned in a travel advertisement written by a Special Galaxy Reporter who had investigated the Great Temple ruins after the Alliance to Restore the Republic abandoned the jungle moon.
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