When we load up level 2, we are presented with this:
Kind of ironic since there's text, right?
Let's once again take a look at the source (this is becoming a thing!):
Hmm, just the normal text... and wait, an image? The <img src...> code is HTML for embedding a picture into a webpage. It's located at files/pixel.png, so we know it's on whatever server is running this webpage.
Let's try to navigate to it!
Well, if you opened it like I did, it's just a white page. That makes sense since it's just one pixel. But we know it exists on the server, and there has to be a folder called files. Lets see if we can get to that folder...
That's something we like to see, a directory listing! We can also see there's another file called "users.txt" in there!
Opening users.txt gives us:
We enter the natas3:lOHYKVT34rB4agsz1yPJ2QvENy7YnxUb on the next level and continue on...