Y Tey, Like Solidify a Little Bit More

Spren are the ideas of collective human experience that have somehow come alive. Sentience is the key link. Spren are sentient creatures that live the cognitive ream, where humans are sentient creatures who live in the physical realm. Shadsmar is where this first happens. And it is their place, meaning the sprens place, although we created it, they shaped it. They rule there, within their own cities.