To get the Mega Glowbo, first you must have the Ice Key and you must know how to use the Talon Torpedo ability. Once you have the Ice Key and this ability, go to Glitter Gulch Mine and hit the switch near the entrance to open the grating which leads to the Water Storage area. Run to the grating before it closes and go inside. Talon Torpedo the big boulder underwater and go through the tunnel into Hailfire Peaks. Climb up the small hill and unlock the Ice Chest to get the mega glowbo!