Finally I have succeeded to come to the part I promises so long ago.
So here it is
Based on The Legend Of Baba Yaga Explained
How the Streel River was born
by RobinThe Ethengerian tale "Vasilisa the Beautiful," tells of a pretty young girl who lives with her wicked stepmother and two ugly stepsisters in the location of future Bargda, Ethengar, close to the end of the Nithian Era. The stepmother runs Vasilisa ragged with increasingly difficult chores, which the girl is always able to accomplish through pure persistence. When Vasilisa becomes old enough to marry (15) her stepmother decides to get rid of her so her beauty will stop distracting suitors from her own daughters. To this end, she sends Vasilisa on her hardest errand yet: to fetch fire from the Great Hakomon Baba Yaga, living on a sandy shore on the southwestern side of Lake Grondheim, where a salty stream flows down the undeep valley neorth nof Gnollistan.
The girl makes her way to the chicken leg hut at the edge of the Lake, where Baba Yaga immediately puts her to work to pay for the fire. The witch sets before the girl a series of near impossible tasks, which she is able to finish each day. Despite being surrounded by eerie sights like disembodied pairs of hands and the Baba Yaga eating inhuman amounts of food, Vasilisa keeps her cool and is polite to her witchy benefactor.
One day when Vasilisa wakes in the morning and spies through the window happening just outside the chicken leg house seeing the firelit dim inside the skull-topped fence posts, and spies a rider dressed all in white galloping upon a milk-white horse around the house. The rider then jumps a wall and vanishes. Soon she spies a rider in red on a blood-red horse who does the same. In the evening, when the Baba Yaga returns to check on Vasilisa's work, the girl sees a rider in black on a coal-black horse galloping around the hut before vanishing like the others. After Vasilisa has done all of the witch's tasks to her liking, the girl works up the courage to ask the Baba Yaga who these riders were. The Baba Yaga reveals that the white, red, and black riders were the day, the sun, and the night, respectively, all of whom she refers to as her faithful servants. Wisely, Vasilisa asks no more questions of the witch.
The witch sets her to the task of spinning wol end braiding a magical sweater. Doing this the first time, she works on late into the night, and the apparently lawful black rider notices the young girl. He approaches her and warns her that Baba Yaga plans to steam two children to death in her bath house, eat them, and ride away on their bones. Vasilia finished the sweater and with the dark rider helps the children to escape in the night. The next day Baba Yaga discovers the children are gone, grabs her cauldron and broom to pursue them.
It's only with the help of the Vasilia who gave the witch the sweater to stay warm in the mountains, and (purposedly) hooked the end thread of the sweater to a skull’s teeth in the gardenfence. The witch went off flying through the bushes through the undeep valley next to Gnollistan, in her cauldron, unaware the thread unravelling the sweater., The thread of the magical sweater was stretched out and slowly the sweater was unbraided as Baba Yaga pursued the children up towards the Twin Volcanoes. Close to the volcano the sweater became fully undone, and fell down. The witch cursed and stopped her flying cauldron to retrieve the magical wol, when a milky white river raged up the mountain towards her. Hating the weird upstreaming warm water she returned home. The children were able to escape the witch’s clutches and returned home. Close to her home Baba Yaga saw the river came from her own skullfence. She ordered her chicken legged house to leave the raging water and saved Vasilia and the witch’s cat from drowning. As staying was fruitless and the new river continued to stream upwards Baba Yaga thanked and gave Vasilisa fire held within a skull, and ordered her to go home and use it for revenge.
Thankfully Vasilisa went home, saw her stepmother and stepsisters glorifying her demise and taken all her meager valuable she had left behind. Vasilia was directly insulted and attacked by the stepmother and the stepsisters. Using the fiery Skull she defended herself from the relentless attacks and burned the Yurt and all within to ashes. Vasilisa barely survived and later married the Ethengerian Khan who helped her to in attempting to stop the fire.
Magical Scientific Explanation;
The starting point of all rivers is normally higher than their end point. However, under the right conditions, small amounts of water can be drawn upwards, against the tug of gravity, through a phenomenon known as "capillary action". For this to occur, however, the water must be confined into a small flow space.
The magical sweater Vasilia gave to Baba Yaga however greatly increased this natural phenomenon. In the end the water was drawn uphill towards the Twin Volcanoes up to a hundred yards away fro the string which came totally hidden in the raging white warm water, and going furth southwest beyond the Twin Volcanoes naturally (ie. Flowing down). Over the following centuries the Lake Grondheim became depleted and the water speed decreased, and took on a normal color around 0AC. From this moment on, it was not directly evident the water flowed upstream. Yes, it was slightly warmer than a river should be, but who would notice this when those who would be able to, do not approach the river except where the water is nearly going horizontal (and thus do not notice), or where the common humanoids are to dumb or totally uninterested why and how a river flows.
Up to this day the upflowing river is fed by the Krandai and Dol Stral and Dol Anur Rivers, and the whole river is named Streel River from the Dol Stral (renamed Dol Streel) to the Malpheggi Swamp.
Yet what will happen when someone rediscovers the magical thread of Baba Yaga’s sweater responsible for the continuation of the upflowing part of the Streel River. That happens in 1026AC and is explained in Threshold 14.
