Performance Blue Moss Camo Sports Jacket
The Twilight is accessible only to Others (both living and dead), particular magical objects, and certain animals. Others access the Twilight by raising their shadow, increasing its volume and density, then stepping through it.
As mentioned before, particular magical objects can enter the Twilight. However, it is not so much that they can enter the Twilight as that they exist on multiple levels of reality. For example, a copper amulet in the human world may be seen existing in the Twilight as a small ball of fire.
Night Watch hinted that animals do not always follow the same rules as humans or Others when it comes to the Twilight. In the first book of Night Watch entitled Story One: Destiny, Anton explains that "For cats there is no [human] world or Twilight—they live in all the worlds at once."
There is only one natural inhabitant in the Twilight, a dark blue moss that grows along many surfaces of the sepia-toned human world in the first level of the Twilight. It feeds off of the emotional energy of Others who enter into the Twilight and of humans in the ordinary world. There is a theory mentioned in the books that states that large colonies of dark blue moss can unbalance the human psyche and cause psychosis but it has not been proven. Nonetheless, the protagonist of the Night Watch—Anton—occasionally feels compelled to utilize magic to burn off the blue moss at points in the story.
Russian author Sergei Lukyanenko.