Oniria is one of the many names for a specific time branch that might contain our version of Earth. Or a facsimile of such.

For the unwary visitor, the most noticeable thing about this particular time branch is how mundane it seems to be; just regular mortals living and thriving with regular technology.

Until they pierce the Veil, and things go crazy.

And not only crazy as weird. Oniria is quite famous for being a horrible cesspool where powerful dreamwalkers can use their gifts with total impunity on the unaware. It is the end state of a total lack of transparency, and it is nasty.