The flora on Yavin includes sense-enhancing blueleaf shrug, climbming fern, feather fern, colorful nebula orchids, blistering touch-not shrubs, and explosive grenade fungi. There is a plethora of indigenous life in its jungles and some which have been created by vistors to its surface.

Many ancient Massassins ruins have been given names, including the Great Temple, the Palace of the Woodlamander, and the Temple of the Blueleaf Cluster; almost all of the ruins are connected by soem underground tunnel complexs. While there are many myths about temples hidden below the surface and inside of volcanos, no one has truelly confirmed any of this. More than 4,000 years before the Battle of Yavin the Sith magician Naga Sadow, under the sentence from the Sith Lord of the time, fled to Yavin 4 with his followers so he could practice his dark-side alchemy in peace. His alchemy helped create many monsters, including a warrior species called the Massassi, designed to guard Sadow's Yavin 4 legacy.

When the Dark Jedi Exar Kun arrived on Yavin 4, he enslaved the Massassi and forced them to construct new temples as focal points for Sith power. during the Sith War, Kun brought 20 Jedit Knights to Yavin 4, where he infected them with the evil spirits of the ancient Sith. He ordered them to go out and slay their Jedi Masters, and terrible Jedi holocaust descended upon the galaxy. Ulic Qel-Droma arrived soon after with thousands of Jedi to stop Kun. Kun sacrificed thousands of Massassi lives to trap his own spirit within the walls of the temple. The Jedi mistakenly ignited the moon's jungles, devistating its surface.

Centuries later, the Rebel Alliance engineers cleared out the ancient structers and made them fit for habitation.