Nebirous is a large creature that fly in the air. His appearance is that of a golden stone statue with flat pieces floating around him, and it is such that Yurick mistakes him for both a coffin and a skeleton.
Boss Battle Edit
He's normally invincible. The strategy to defeat him is to shoot him with silver arrows to make him vulnerable for a short period of time and attack him with everything you've got. Obtaining the silver arrows is very simple, you just have to kill his minnions (undeads) and they'll drop silver arrows for you to shoot. You can also buy them Zoran's shop in chapter 36.
When he is invincible he'll chase you through all the place, but when he's vulnerable, you'll have to chase him all over the place. Some of the other mercenaries yell at you to corner him, saying half of you should go one way and the others go the other way around. This hardly works, though, because he just goes past you all.
After defeating it you get the Death scythe.
He is also a boss fought online in Multiplayer. He has more health, defense, and it takes 3 arrows to break his barrier. Once you break his barrier, you can shoot another Silver Arrow to paralyze him, that way he won't be running away from you for a short period of time. After half of his health is gone, he turns red and "enraged" as if you get from his attacks without guarding, he can insta-kill you.