Inside the folded card, you will find a secret code that works with the Marvin’s Magic app, which you can download free from the Apple and Google stores. Scan the code, and you can access a video that appears to be an X-Ray view of the Spider Trap.
With the victim holding the Spider Trap on their open palms (see last couple of Wicked Pranks), place your phone on top of the Trap while the special video is playing. The spooky illusion created is a large spider crawling around on top of the Trap, before vanishing.
Where did the animated spider go? Well, if you have set up the Ultimate Spider Scare as described earlier, your victim is about to find out!