Chamber 6: First Return to East Wing: Middle Fog Chamber
Head back into this foggy chamber and run to the middle of the room with the Sphere. Place it on the ground, and deliver some slashes to the Twilit Keese and Messenger. Don’t bother finishing them off; that Hand is on its way! Drop the Sphere in the groove again, then run and stand on the steps before they ascend too high for you to reach, and climb to the top. As soon as you’re on the high southern ledge, Clawshot the Sphere and leave via the southern door.
Chamber 5: First Return to East Wing: Lower Chamber
You appear at the lower chamber’s northern ledge, but there’s no way to reach the floating light platforms ahead. Instead, you must jump into the shadow cloud, ignoring the pots for the moment, and then turn around. Look for the dark globe at the base of the north wall, and stand by it. The light from the Sphere brightens the globe into a white beacon, and two more light platforms appear on either side of it. Ride them up, face south, and carefully leap to the light platforms to escape.
At the south end of the light platform route, don’t drop by the two globes, as you’ll have to retrace your steps. Instead, wait until the globes shine, creating a new light platform, and ride this to the exit.
Chamber 1: Second Return to Ethereal Plateau
Stand on the light platform. Ride it to the circular plateau, and run around the circumference. You can now change the remaining Twili to their normal forms, as both the Spheres give off considerable light. Then place the second Sphere into the circular groove. Light floods into the blade of the Master Sword. Now inspect the Twili you saved from the shadows!
Master Sword
Light filled the Master Sword!