LDB
The rest of this level was originally an image leading to a YouTube URL. Past that point, you would need to go through five total videos in order to complete level LDB, in which the step to finding the answer in each video is barely visible letters/words that would only appear for a few frames. I don't know what I was thinking when making the rest of this level including part of the last level (which does that too) but only the rest of this level will be removed from the puzzle, even though the last level is basically the same thing, the last level does have a nice atmospheric layout including ACTUAL puzzles!! The answer to reach the last level is in the source code.