kengr

We've been doing something similar with the Ravenstone series. Some parts of the multiverse have magic, others don't. Not all worlds have the same kind of magic. A couple characters in book 6 have magic that imitates some of the old fashioned physics ideas like phlogistons, and does some other weird things with a "mad scientist" steampunk aesthetic.

Similarly, there's at least seven different ways to traverse the multiverse: learned magic method (faery only), natural world walkers (rare), world walking powered by more magically powerful allies, magical portal devices using runes, "blue sphere" portal devices, ships that travel the void between the worlds, and a non-magical portal device by a new character from a LOOOONG way away from the main universe... from a universe without magic.