| Category | Swamps |
| Continent | Brucrumus |
| Region | Lands of Purity, Troll Bogs |
| Map | Sinarag Swamp |
The extensive Sinarag Swamp occupies territory spanning the Troll Bogs and the Lands of Purity. This vast wetland complex emerged over millennia, formed by the otherworldly waters pouring out from the Radullu Rift. By the Horgon Era, the influx of water, sediment, and vegetation through this rift had transformed a significant portion of the Troll Bogs into a sprawling wetland ecosystem, with Sinarag standing as the largest of these wetland habitats.
Sinarag is the domain of yuan-ti, Lorhazi, Scrag, black dragons, trolls, catoblepas, will-o-wisps, crimson deaths, and other wetland terrors. The region is replete with these perilous creatures that inhabit the treacherous marshes. Travelers must exercise the utmost caution when venturing into this foreboding realm.
In the Lith-Crillion Era, the Pyramid of Alchemy was constructed in the southern reaches of Chen'gom. The laboratories within this partially submerged structure were utilized to generate a variety of novel lifeforms unique to the Troll Bogs. Predominantly, these were variations of species indigenous to Sinarag, although some were entirely new creations. The Lith-Crillion researchers also initiated a program aimed at selectively breeding trolls, with the objective of enhancing their intellect and potentially mitigating their violent tendencies. However, these endeavors did not come to fruition, as it was determined that the process would require an impractically lengthy duration, estimated at several thousand years. It is widely believed that the Lith-Crillion personnel engaged in these activities were inspired by the demon laboratories at Aša Abrai.
Sinarag is purported by Ningizzida. This is a precarious assertion, with borders exceptionally arduous to govern even by the empire's aquatic inhabitants.
The disease and malignancy of those dwelling in this immense swamp are such that the location has routinely been evaded by conquerors. The undead legions of the Black Tide of Thasmudyan eschewed it, as did the sacred empires of the Lands of Purity. Virulent maladies, sink holes, acid pools, insect infestations, toxic fumes, and a multitude of beasts deter even the intrepid from this domain.