Breaking the Siege of Kvatch

Enter into Oblivion through the firey gate. Once inside you discover a hellish world surrounded by lava. The basic procedure of deactivating an Oblivion gate is: Climb the tower, find the keys to open the right doors, and take the Sigil stone at the top of the tower. Note that throughout Oblivion are semi-rare ingredients, especially Bloodgrass. Take this chance to collect as much as you can, so that you won't have to make any special trips into Oblivion when in need.