Place it under the transformation itself, after a quiet build and before the reaction shot. Follow it with a bell ding sound effect for a single clear accent, or swap that follow-up for an anime wow sound effect when the reveal is played for comedy.
About this sound
This is an 8.8-second fairy tale magic sound effect built from bright, sparkling chimes and a soft shimmering sweep. It feels light, enchanting and hopeful, like a spell has just worked or a hidden door has opened, giving ordinary moments a gentle storybook glow without any voice or dialogue.