Gura, Black Knight, Gothmog, Barold, Ork and others were part of a fellowship. One day, Gothmog got corrupted by his Horns and wanted to destroy Black Knight and Gura. He told Barold about this plan and Barold attack him. They fought which resulted in Gothmog being destroyed and Horns of Corruption falling on Barold and making him tiny.
Gura and Black Knight later arrived at the castle and found the ashes of Gothmog; Black Knight took the horns for himself and Gura left to go the mountains.
And now, somehow, Gothmog is back.