The outermost temperate planet of the Ando system maintains a hospitable environment due to its very thick, foggy atmosphere. This phenomenon holds the solar radiation that reaches the planet close to the surface in a thick fog. Within 4 km. of the surface, the atmosphere is almost non-existent, and even such elevations as 1500-2000 m. above sea level are too cold for human survivability. As such, most inhabitants and visitors stay on the open plains that cover 35% of the surface of the planet. Liquid surface volume of the planet consists of about 45%, the remainder being low hills and mountains. The planet's surface is very rich in silicates and ammonia phosphates, attracting several mining interests over the years.

This planet was the only one in the Ando system that humans ever took an interest in colonizing, though they were largely based in the oldest city on the planet, called Artheraron. There were many mining villages and farming communities, however, though all the goods wound up passing through the capital city’s spaceport.

The Old Republic maintained a military listening post on the planet, to keep an eye on the wayward Aqualish, which was later taken over and upgraded into a full Imperial Army garrison after the Empire took control. The Empire placed strict sanctions on offworld trade and siphoned off much of the raw materials mined to fight the Rebel Alliance and squeezing the once-thriving local economy with back-breaking taxes to fund the war effort. The whole thing came to a head after three members of a well-respected mining family were arrested for being rebel sympathizers. A large number of farmers and miners revolted, overrunning the Imperial garrison with a mixture of surprise and sheer force of numbers. The Imperials retreated into orbit and pounded several major towns with orbital strikes from their turbolasers, causing over twenty-six thousand casualties, until the leaders agreed to give themselves up. It was the first and only insurrection, and the Imperials increased their stranglehold dramatically afterward.

Eventually, the Empire was displaced by the Falleen Federation Navy after a brief but bitter fight, and the garrison was downgraded to a listening post once more, keeping a safe watch over the people of planet Horos against those who would threaten their freedom again.