An unknown dimension where only the consciousness may tread.
There are two main 'natural' appearances to Dreamspace, one is a field of bronze grass and a sky resembling a sunset, while rain falls upwards with pockets of dust. One may also find oceans and rivers made of liquid metal. The other is a realm of rain clouds, both the land and the sky and makes up what can be called 'outer space' in this dimension. Regardless of where one is, there is always light, even though there is never a visible natural source.
Dreamspace is a pocket universe that is rarely noticed by most advance civilizations and unreachable by primitive races. It is a matter-less realm where physical bodies cannot enter, instead only minds may enter, creating their own 'mental avatars'. This means visitors, dreamers can manipulate the environment, warping it as their imaginations desire.
It is not known where the dimension comes from, but it covers the length and width of the galaxy, possibly even the universe.