A marshy region within Tarn, fed by the Grand Tolkarsus—a massive river that stretches from the Nirvanis Mountains (part of the Kharvorn range) in the northeast, flowing southwest through orcish territory, west of the Wurmspine Mountains and the Deadwalk desert, eventually reaching Cykravikus Lake. This colossal lake connects to Symonair Lake, which empties into Phyndarr Sound at the northeastern edge of the Shattered Sea.
Within Plenjorn Swamp, the river's waters are said to possess miraculous healing properties. Bathing in the Grand Tolkarsus can cure even the most brutal wounds and life-threatening injuries. Few outside Tarn know of this power, and the Tarni orcs fiercely protect the swamp from outsiders, ensuring the healing waters remain a secret advantage for their people.