This papercraft is Headless Horseman, based on the MMORPG game World of Warcraft, the paper model is created by Skily. During Hallow's End, the Headless Horseman is a summoned elite boss spawned in the Pumpkin Shrine in the middle of the Forlorn Cloister in The Graveyard, a special seasonal instance of the Scarlet Monastery. Additionally, his shade attacks Horde and Alliance villages at various times throughout the event.
The Horseman was once a knight of the Silver Hand, but is now cursed. He is of the belief that he is alive, while those who face him are dead. When defeated, he is revealed as Thomas Thomson (aka Sir Thomas).
After using the Dungeon Finder and entering the graveyard, click on the Pumpkin Shrine to summon him. Each character can summon the horseman once per day. [Source: wowwiki]
You can download this papercraft model here: