RyiXy'an

RyiXy'an also known as Hyoton III, is the former homeworld of the Xi'an race. The planet's atmosphere was destroyed in the Xi'an civil war in 19755 BCE, rendering it uninhabitable. The name can also be written as RyiX'yan in Standard Romanised Xi'an.

Atmosphere
The atmosphere was destroyed during the peace talks at end of the civil war in 19770 BCE, when House Kl.ō attempted to assassinate the leadership of Houses Chii, Ru'a and Uai'i by sabotaging the local weather satellites. Instead they turned the entire world into an uninhabitable smog planet, as it remains to this day.

Environment
The planet's flora and fauna was described as a 'lush' tropical world with a hot and humid climate. It was also home of the later domesticated species called Yengi. It has an orbital period of 1.28 Standard Earth Years.