While the Alliance and Horde were focused on defeating the Lich King, Cho'gall began the resurrection of his new master, the Old God C'Thun, monstrously deforming the ogre's body in the process.
Med'an and the New Council of Tirisfal defeated Cho'gall using Atiesh, Greatstaff of the Guardian, burying him beneath the rubble of Ahn'Qiraj.
I'm not sayign its C'thun, but im proving the point that c'thun IS alive.