Impenetrability is a concept in physics in which two bodies cannot occupy the same place in space at the same time.
You show two playing cards of different colors in a crossed position. In the blink of an eye the front card crosses and passes through the back card. it's fast and amazing.
Simple to do and everything is explained in detail. An extremely visual and impactful effect that can be repeated over and over.
This can be done both for live performances and for social media, your viewers will watch and will surely ask you to repeat the magic.