Oslira – roughly 1600 km from her source in Dragon Pass to her mouth in the White Sea. Perhaps the mightiest of the River deities, she is the mighty Blue Dragon that tried to drown the lands in the God Time. Defeated by Yelm (or his son), she was tamed by Lodril and his sons and is now one of the great fertility deities of Peloria.
Tanier – the great river system of Ralios and Seshnela, he runs roughly 1600 km from her source near High Llama Pass to his mouth in Seshnela. He is even mightier when his tributary the Doskior is added – that river is some 1450 km long from its source in the Mislari Mountains to its mouth in Lake Felster. Tanier is revered by all the peoples along his banks as the Source of Waters and is associated with Sramake, the Great River.
Janube – this river flows some 1450 km from the Sweet Sea to Sog City. The Janube has many small cults along her bank, including a fertility goddess, a war goddess, a death goddess, and a renewer goddess.
Engizi – this river is much shorter than the others, only 675 km for his source at the Skyfall Lake, but is of cosmic significance due to his close association with Heler and Lorion the Sky River.
Pamaltela? There are some comparable sized rivers such as the Baruling, Ediruss, Riogache, Sabaki, and Sinjon, although most of the big rivers in Jolar and Kothar are seasonal.
