Enter the Chamber of Living Portraits in the center of the Enchanted Kingdom's Palace.
You will see a statue of Thorn, who is holding an orb with a hole in the middle. In the hole is the Eye of Strength.
Morph into Thermite, and then approach the statue.
Aim a bomb shot so that the bomb will either hit the orb or go into the hole where the Eye is.
If done successfully, the statue will explode and the eye will drop to the floor. Then simply move to the pedestal to pick it up.