Solid through solid in a way that looks like it's straight out of Harry Potter.

When Harry Potter heads off to Hogwarts, he must pass through a solid wall on platform 9 3/4. At least, the wall looks solid until he charges toward it and a door appears. Once he passes through, the door disappears as quickly as it appeared.

Now, imagine that...but with a coin and a playing card.

You draw a line on a playing card. A coin is then introduced (or borrowed) and placed on the line. Impossibly, it passes right through as if there was a slot. You then remove the ink and show the card is solid. No ink or slot in sight.

It's a wild bit of mind-bending card magic and close up magic that you can start building right now.

"Ink Permeation" is easy to perform. However, the DIY required is best suited for someone with more intermediate gimmick-building skills. While someone who is brand new to magic DIY could very likely build this, they might find it more challenging than an experienced gaff creator would.