Earth-90 is the Universe in which all things Brywarrior take place.
The dimensions to be used/being used in BBO and beyond.
The Prime Timeline
This is the home Dimension to Bryce Bowman. The events of Bryce Bowman: Origins take place in this Dimension, aside from the occasional appearance of an outside force, such as John Smith or Black Scythe.
Bowman 10,000's timeline is within this Dimension, but is separate from Bryce Bowman's current future.
Black Scythe's Home Dimension
The events of Bryce Bowman's life take place here.
This is a Dimension briefly hinted at in the episode Bowman 10,000 (Episode).
Azmuth's Home Dimension
It is known that Azmuth is not from Dimension 1, but rather a currently unknown Dimension. We have designated his Dimension as "Dimension 0" to say that we really don't know where he is from.*