The rivers of the Twilight lands are all tributaries of the One River, which is fed from the ice of the Dark Side, thus the Black Order’s magic can control them, altering their courses to flow where they will. With this spell a river can be bent up to 50 strides away from its course. Alternatively its sources can be made dry, reducing its flow by a third, or enhanced, increasing flow by a third. Either effect lasts only so long as the Mage sacrifices one man and one woman a day, or the spell is bound to an Obsidian Sphere.
power+15 strides deviation or an additional 1/3 alteration per power level.