How to find Lucid Nightmare Mount | Part 3: Ahn'Qiraj
The third part takes you to the Temple of Ahn'Qiraj raid dungeon. Reach C'thun's room. On the left side of the room's map, behind the 3 imprisoned dragons, go up the stairs. Click the Mind Larva. A Bejeweled mini-game starts. CORRECTION: Move pieces until you line up 5 pieces of the brain icons. Then a scroll spawns next to the Mind Larva.