One of the many trademarks of a Magical Girl Anime show is the transformation sequence. This is the bit of stock footage accompanied by a peppy BGM that changes the ordinary young girl into her Magical alter-ego. She is surrounded by everything from flashing colors and ribbons, to wings, balloons, and bubbles. In shows for younger audiences, the transformation sequence is usually fairly modest, with the girl being surrounded by glowing energy that obscures her form, or by some kind of cape or modest dress. You can usually tell if a magical girl show is for a male audience if the transformation sequence includes panty shots or other more revealing flashes of skin.
A transformation sequence is pretty much shown in every episode, sometimes more than once, so the animation during it is usually of a bit higher quality than the animation in the rest of the series. A good transformation sequence will not bore the viewer. With stunning animation and an exciting BGM, a good transformation sequence is entertaining with every viewing.
Common questions about transformation sequences are: Why do they take so long, and what are the bad guys doing in the meantime? Why don’t they just attack during the transformation, when the girl is vulnerable?
Well the answers to these questions can be a little vague. The sequences take so long and appear in every episode for many reasons, including giving the animators less actual animation work for each episode. It has been generally accepted that transformation sequences are actually much faster than they appear to the viewer, They are so fast, that in real-time they don’t last much longer than a second, or the blink of an eye. The villains usually have very little time to react. This same theory also applies to Magical Girl attacks. They are also accompanied by a standard length of stock footage and BGM while the Magical girl charges up her weapon and lets fire her power.
Occasionally the Magical Girl is attacked in mid-transformation, but this is very rare. To save time, transformations can be cut short, combined with the transformations of other Magical Girls in that show, or omitted completely. One of the highlights of any Magical Girl show is when the heroine gets a power-up that results in a new transformation.