Red, white and black riders

These riders are armored warriors dressed in their respective colors, and riding steeds that match those colors as well. They substitute for heavenly bodies in the Otherworld, and every time they ride by, the time of day changes. The red rider is the dawnbringer, the white rider changes dawn into day, and the black rider causes the land to be bathed in darkness.
The riders appear to be in the service of (or at least somehow connected to) Baba Yaga. As each ends his daily ride, he and his horse disappear beneath the gate of the crone's bone-wall compound. In the morning, they ride out from under the gate as well.
None of the Yokels have ever spoken to any of the riders, and it is not clear whether they can converse at all, or do anything else other than make their daily rounds. On several occasions, they did discover valuable items that were either dropped by the riders, or simply happened to lie on the path where the riders passed.

Current Location

The Otherworld