Ghost Ink by Red Dragon

The magician asks a spectator to draw a card from a deck and sign it. The card then disappears into the deck. The magician then uses a marker to draw a black line on the back of the card at the top of the deck. A magical gesture, and the newly drawn line visibly disappears! Upon reviewing the cards, it becomes apparent that the line has magically been transferred to a card in the center of the deck... the card signed by the spectator!
A breathtaking effect!
• The ingenious gimmick is created with Bicycle cards.
• For better visibility of the black line, the gimmick comes with a red back.
• A link with detailed Red Dragon video instructions is provided. The instructions are in Italian, but thanks to the video, how the trick works becomes clear even if you don't understand Italian.