On occasion, Dimensional Rifts will open. Mystics are very handy to have around because some of them have learned the skill of weaving the Fabric of the Veil back together, often using a bit of themselves in the process.
Dimensional rifts allow beings to cross willy-nilly, and while this sounds charming and all, it also means that those from the other dimensions can cross over to here, and they are not often friendly. Indeed, they are three times more likely to be unfriendly or upset at encountering a rift – especially if they get trapped on this side of it.
Dimensional Rifts are, however, rarely directly encountered or approachable. There is usually some quirk to them, such as spinning widdershins thrice or coming from a very precise direction after having done certain things in a certain order. This can make locating them very challenging in order to begin closing them.
It is not wholly uncommon for those who use magic to carve out distinct, separate Demiplanes themselves, and perhaps even affix those spaces to objects. These spatial distortions are themselves Demiplanes – and often do not have constraints such as time or vacuum in them; they may also not have air and space.