LolSecret levels are levels you usually can't access by normal means, meaning they don’t have a direct passage leading to them. It is theorized there are still many more secret levels to be found out there.
The Basement
The basement was formerly theorized to exist at the bottom floor of the backrooms, but there's no evidence that there is a bottom. Due to this, the former level -1 has been renamed to "The Basement" after another level was named -1. To access this level you have to break and go through the roof on any floor. This level is the most dangerous of all, yet highly skilled people still come and go through this level. The exits to this level are random; the same as the paths to them. People mainly come here to try and find an unknown base.
While the basement appears to be composed of an endless stairway, people can often end up in the negative levels while exploring it. If you're coming down here, make sure to remember the most stable parts of Level -1 and Level -2, it might save your life.
The Metro
The metro is a recently found level that you can access by getting on a train and conducting it through its tunnel. The metro is extremely peaceful and holds another unknown base. The exits are random but the paths are stationary, making it mappable, although not much has been mapped.
The Dark Metro
Occasionally, after reaching the Metro, you may find a strange, dilapidated house from the Victorian era. Entering it will transport you into the Dark Metro, an older and more sinister version of The Metro.