| Category | Marvels, voidships |
| Type | Helas Vessel |
| Continent | Brucrumus |
| Region | Troll Bogs |
| Alias | Kythac Helas |
| Owner | unknown |
| Built | 28 Lunar 1795 DE |
| Map | Chen'gom |
The Spire of Rioch Tetrax is a Helas Vessel class voidship. In the Horgon Era, this primordial-built structure resided on Osâchar. On that world, it served as the palace for a Saint of Maen known as Rioch Tetrax. During the Second Suellk Invasion, Osâchar faced an illithid incursion. In 537 HE, the Helas Vessels departed Osâchar and ventured into the Void. This marked the end of Horgon (159 HE - 537 HE) civilization on Osâchar.
A little more than three centuries later, 862 HE to be exact, the Helas Vessel entered Bal-Kriav's atmosphere. One of these was the Kythac Helas, better known today as the Spire of Rioch Tetrax. It landed in the southwestern part of Chen'gom. It descended into Mount Orngrek, a dead volcano, the new home of its passengers. In an area of mixed light and absolute darkness, an area they named Tûnin-Gil, the Durkoth leader Rioch Tetrax and his Durkoth turned to nation building. Their center of power was based out of Nagdúrzol. The army of these new arrivals was several thousand storm archons called the Laupha. The support staff, the workforce, and soldiers when needed, were nearly 12,000 Dromite slaves.
The Spire of Rioch Tetrax, akin to other Helas Vessels, possesses an ethereal and extraordinary appearance - a surface darker than the moonless sky. Under a torch, one observes the light bending towards the Spire. This distortion is often so pronounced that magical illumination is extinguished, and even ordinary torches and lamps become almost ineffectual. Yet upon entering the Spire, normalcy resumes.
The Spire of Rioch Tetrax derives its power from the psyche of Kythac Helas - a living, sentient engine spawned during the Creation War by the primordial Beldileck.