If you are a Potterhead, you must try this experience. Just show your online ticket, you can enter HP:vision of magic. After that, you will be lent a wand that you can use according to the instructions (the staff there will explain how to use it). The staff will regulate the number of visitors who are allowed to enter (in turns) so that the place does not feel crowded, although that means the queue to enter will also feel longer.