Headless Horseman

The Headless Horseman will spawn randomly anywhere in the world between 10:00 p.m. and 5 a.m. usually riding his ghostly steed. He will occasionally stop to let you examine him and will continue riding. He is occasionally spotted off his steed running after it. The Horseman performs no actions, and cannot be harmed. Currently the only things that the Horseman has uttered is "Finality", "Such an abrupt end to our game", "Who dares disturb my rest?" and "All the living shall fear the dead.". If you continue to follow him, he will normally lead you to Hamvir's Rest. There you can find three skeletons, a leveled Draugr, and a master-level chest, as well as a couple of items in the area. He is depicted wearing Steel Plate armor.

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 * In fact, some tests have shown that, if you go directly to Hamvir's Rest, the Headless Horseman can be seen during daytime. He's going to be standing at the entrance of the cemetery, and will not move until you get out of his sight. That means he will not go out on his random walking.

Known spawn locations

 * If he spawns off his horse it is possible to steal it and ride it much similer to the unicorn in oblivion
 * Coming down the road from Meridia's Beacon, heading towards and over the Dragon Bridge, 4:38 AM, 27th of Heartfire.
 * Road leading from Anga's Mill to Forsaken Cave at 4:35am, 5th of Sun Dusk.
 * Road between Falkreath and Helgen at 10:20pm, 24th of Last Seed.
 * Road by Honningbrew Meadery.
 * At Dragon Bridge, heading south, chasing his horse at 10:49 pm, 4th of First Seed, also 12:08 am, 24th of Heartfire.
 * On the road north of Gloomreach traveling up the pass at 11:28, 24th of Last Seed.
 * At the signpost immediately south of Falkreath Stormcloak Camp at 11:59 PM, 10th of Frostfall.
 * On his horse near the entrance to Labyrinthian.
 * The road that leads to and around Fort Kastav.
 * The road the leads to Salvius Farm from Kolskeggr Mine at 2:30 am of First Seed.
 * At around 11pm 5th of Sun's dusk from Blind Cliff Cave to Salvius Farm he comes about and double backs as he nears the farm, he runs on the same road till he crosses the bridge near Kolskegger Mine.
 * Road leading from Steamcrog Camp to Kynsegrove, Eastmarch.
 * On the road along the norhern coastline between Broken Oar Grotto and the northeast exit of Solitude at 11:45 pm.
 * On foot at Hamvir's rest running south east.
 * On a path between Morthal and Labyrinthian.
 * The road between Markarth and Falkreath.
 * North of Robber's Gorge heading south on the road riding his horse at 5:00 AM 7th of Heartfire.
 * Hamvirs Rest on horseback.
 * In the forests surrounding the Lord Stone.
 * Outside the main entrance to Solitude.
 * On the road heading south near Wolfskull Cave and the Statue to Meridia
 * Saw him cut out of the wilderness and onto the road just north of Rorikstead, heading south.
 * On the way to Dustman's Carvin.
 * On the road near The Steed Stone
 * East of Helgen
 * Found him in the Wilderness above Riften, about 3 miles away.
 * Going towards Falkreath just past midnight of the 15th of Evening Star.
 * On the path outside Fort Greymoor at 11.30 (found after killing Agnes for a Dark Brotherhood Contract)