Yes, some Villains push black light floodlights. This black light makes their costumes glow in the dark when they do the evil show stop.
Fantillusion Parade features 3 show stops:
The first is where the first floats have a white lightshow and Chip, Dale, Goofy and Pluto come out of one floatand have a dance.
The second is the evil one. The Villains steal the light and transform. E.g. Maleficent transforms into a dragon, Jafar into a snake and so on. This show stop also includes the dancers with the black light.
Finally, in the third stop, the Princesses and Princes win over the Villains and have a dance in the light. In my opinion this is a very touching moment.
Unfortunately, the parade does not do each stop at each point of the parade route. As a rule of thumb, usually the best spot to see them all is Central Plaza in front of the castle. But the exact positions of the stops vary.
When there are bad weather conditions like rain or a strong wind, the parade will not do any stops for technical reasons.
Signs that the parade will not do any stops are:
Open curtains at the float of Chip, Dale, Goofy and Pluto so that you can see the characters while the float is moving.
The dancers in the evil part do not wear black robes so that you can see their costumes whiles the floats are moving, or they do not push black boxes.
Sorry for my bad english! I hope this explanations are handy to you.