JOHN: are you sure you can't make it go any faster?
JOHN: i mean, not to sound too demanding, but…
JOHN: didn't you say you can teleport stuff?
JOHN: why not teleport us there?
JADE: i cant!
JADE: not here, at least
I thought as much. Jade's powers probably don't work in the Furthest Ring, because if they did, she could have brought Rose, Dave and the trolls to this Prospitian ship during Cascade. Her teleportation is probably limited to contiguous areas of conventional space, and the Hussieverse is anything but conventional.
JADE: becs powers draw from the green sun
JADE: and the green sun presides over our universe
JADE: many universes actually! and the sessions that created them, as well as the sessions created within them
JADE: including the trolls universe and their session
JADE: think of it like a giant solar system, but instead of planets revolving around the sun, there are many universes
Back when Rose was outlining the Tumor plan to Dave, I referred to the Green Sun as a core of reality - and it seems that's even more true than I thought.
In addition to powering the First Guardians' magic, the Sun also serves as the metaphysical nexus point of all Sburb-generated universes, as well as their associated sessions. Since we've never been given any reason to believe that non-Sburb universes exist, the Sun appears to 'preside' over all possible universes.
It almost sounds like the Sun is reality - and its creation was masterminded by Doc Scratch. The more you think about it, the worse it gets.
JADE: so, bec was able to teleport anywhere in the universe he wanted in an instant, much faster than light
JADE: jack was able to do this too, within our session, and then when i inherited those powers from jadesprite, so could i
JADE: but we could only teleport locally
JADE: which means, bec could jump to anywhere in our universe, but not to another universe, or into a session
JADE: and jack could jump to anywhere in our session, but not outside it
In other words, First Guardians can only teleport to locations they could physically travel to, from their current position.
During Cascade, for example, Jade could teleport to anywhere in her session, but it was impossible for her to reach other sessions, because those sessions didn't have a consistent physical location relative to her own. Similarly, Bec could teleport from Earth to anywhere else in his universe, but not into sessionspace, for the same reason an observer on Earth couldn't point towards a Sburb session. They're on different planes entirely.
tl;dr: to reach a given location via Space, Jade needs a well-defined direction to move in...
...and since moving to another session involves Furthest Ring travel, no such direction exists.
JADE: we cant even jump to the green sun itself, even though we sort of serve as a gateway to it, and all its energy
This, I believe, is the one notable exception to the rule above.
No matter where they currently are, a First Guardian can always open a portal to the Green Sun.
It doesn't sound like they can enter this portal themselves, though. Well, I suppose that makes sense - after all, they are the portal, and you can't move through your own body.
Could Jade reach into that portal, and fetch someone from the Sun, though? I suppose if that was possible, Jack would've just pulled Aradia right back out again, so I think the portal is completely inaccessible to the Guardian who embodies it.
JADE: and once we leave the suns domain, our travel is limited by the speed of light, like everyone else!
JADE: for example, the furthest ring is not in the suns domain
JADE: it is more like the suns medium, allowing it to exist
The Sun's domain includes, at minimum, every Sburb session in existence, alongside every universe they've produced. The Ring, however, can't be a domain, because it's not really part of conventional reality.
Yes, it may be the scaffolding on which reality is built, but the scaffolding is not part of the building.