In the early 2000s, long before modern viral trends, a simple photo of a door appeared on a website with a cryptic instruction: "Don't go to level 2." This was the start of . By the time players reached Level 4, they encountered a puzzle that required more than just clicking—it required looking into the "guts" of the website itself.

: On Level 4, the user had to check the source code to find a hidden link to g4.zip .

: Upon opening the image inside the zip file, the hallway looked empty. However, the true clue was only visible by brightening the image using a photo editor.

: Changing the address bar to navigate "forbidden" directories.

This specific file became a rite of passage for early internet detectives. It taught a generation of web users about: : How to peek behind the curtain of a webpage.

The name "g4.zip" was a hint hidden within the page's source code. Players who figured this out were directed to a downloadable file containing a picture of a . The "informative story" hidden in this level is actually a lesson in steganography —the art of hiding information within other data. How the Puzzle Worked