In this video I'm using an Arduino to run a Simon Says type game that could be used as a puzzle. When the desired level of difficulty has been reached, the puzzle could trigger an effect or code. I use Morse code to send tones that form a number code.
Buy LED arcade buttons:
Yellow - https://amzn.to/2LUAJVN
Red - https://amzn.to/2QqkOo3
Green - https://amzn.to/30b18UE
Blue - https://amzn.to/32Lh55J
Arduino Nano: https://amzn.to/2QcOFQy
Nano Terminal Shield; https://amzn.to/30ddhZj
A big thank you to http://3dPrintingCanada.com for partnering with me to supply filament and other supplies for my 3D printing videos. If you're in Canada and need 3D printing supplies and equipment, they carry a great selection of products for excellent prices and shipping rates.