Star System UX-13 is a star system charted by Kitsurugi Uesu during his departure from Central Yamatai. It is a strategic location in that it watches over the northern gate of the Ketsurui Military Sector and has a habitable world, Forge.

The First Expeditionary Fleet colonized UX-13 I in YE 30, building the UX-13 Training Center (Fort Ready II)

The Yamatai Star Empire placed a global communications network of Emrys Satellites into orbit of the system's terrestrial world in YE 36.

In YE 41, the UX-13 star system was conquered by forces from the Interstellar Kingdom Of Kuvexia during the Kuvexian Invasion of YE 41.

• Type M1 V Red Dwarf
• Radius 2.95 x 105 km (0.42 x sol)
• Mass 7.08 x 1029 kg (0.36 x sol)
• Temperature 3200 K
• Luminosity 1.26 x 1025 W (0.03 x sol)

• Type Terrestrial World
• Orbital Radius 2.50 x 107 km (0.17 AU)
• Period 1.00 x 103 hours (0.11 earth years)
• Physics Large iron/silicate
• Hydrosphere 45 % water, 16 % ice
• Atmosphere Standard breathable
• Biosphere Prokaryotic microbes
• Special Large moon