@Ray Aznable I forgot to add water, thanks.. I have added an alternative card in the first comment.. thanks for P, C & R
@Iskandar - What tricks are required? I don't want to watch the video to find out? Maybe none - just asking... EDIT - Okay - no tricks are required.
@Meko Guy I'm not sure if I'm right ... but inside is a section where B stands on a rolling ball. then there is a part of body B pushed using a mechanism.