Mythosaurs, colossal entities, once roamed the Outer Rim planet of Mandalore. The Mines of Mandalore served as a mythosaur's den. Legends claim they were subdued and mounted by Mandalore the Great along with ancient Mandalorians, yet presumed extinct well before the Mandalorian cataclysm. However, at least one mythosaur endured, dwelling within the Living Waters during the era of the New Republic. Their skull became an iconic Mandalorian symbol, often adorning Mandalorian armor.
Mythosaurs were aquatic sea creatures of immense size, capable of reaching lengths surpassing 30 meters (100 feet). They possessed yellowish scaled hides, black eyes, and prominent horns extending from their mouths. These creatures could thrive both on land and underwater. Mythosaurs employed their formidable tusks in combat, either against rivals or potentially to capture prey. The exact nature of the mythosaur's biology remains debated: was it a slow-moving apex predator, or a swift and agile hunter?
The mythosaurs inhabited the Outer Rim planet of Mandalore, making their lairs within its mines. According to legend, mythosaurs were the dominant species on Mandalore before the Mandalorians established their presence. Mandalore the Great and the ancient Mandalorians purportedly tamed and rode them. Some accounts detail the taming of these beasts, while others describe the even more impressive feat of riding them while they remained untamed. They were thought to have vanished long before the Mandalorian cataclysm, although one mythosaur managed to survive.
Despite being considered extinct, the mythosaur's legacy continued through its skull emblem, a traditional symbol in Mandalorian iconography, often featured on Mandalorian armor. The creature's name was also shared with the mythosaur axe, a melee weapon utilized by Mandalorians. One such axe belonged to Vera Beroya and her father.
In 9 ABY, the Ugnaught Kuiil was instructing the Mandalorian bounty hunter Din Djarin on riding blurrgs on Arvala-7. He chided him for his reluctance, reminding him that his ancestors had ridden mythosaurs, making blurrgs comparatively easier to handle.
During the reign of the New Republic, Mandalorian songs of eons past prophesied the mythosaur's resurgence as a herald of a new Mandalorian age. Lady Bo-Katan Kryze discovered a living mythosaur in the Living Waters beneath Sundari's ruins within the Mines of Mandalore, while rescuing Din Djarin after he had fallen and was drowning. She then kept her sighting of the mythosaur a secret from Djarin. She later requested the Armorer to incorporate the mythosaur symbol onto her new pauldron in place of a Nite Owl emblem. Upon hearing Kryze's account of the mythosaur encounter, the Armorer interpreted it as a significant vision, stating that followers of the Way often experience such visions.
Subsequently, she regarded Kryze's claim as evidence of the new era foretold in the songs. Following the reconquest of Mandalore from Gideon's Imperial remnant, the Mythosaur continued its existence within the Living Waters.
The Mines of Mandalore once served as a mythosaur lair. Legend states that Mandalore the Great tamed this mythical creature. By the New Republic era, they were believed extinct, yet a mythosaur lived in the Living Waters beneath the Mines of Mandalore, within the ruins of Sundari's Civic Center.
A mythosaur skull was displayed on a wall within Dok-Ondar's Den of Antiquities located in Black Spire Outpost on Batuu.
The mythosaurs were initially identified within the current Star Wars canon in the thirty-second edition of the magazine Star Wars: Build the Millennium Falcon. Their first appearance in a visual medium was in "Chapter 18: The Mines of Mandalore". The species originated in the Star Wars Legends continuity, conceived for the 1982 comic book Star Wars (1977) 69, authored by David Michelinie.