"So," says Bella to Rúmil one afternoon, "a few weeks ago I told myself that if in a few weeks I had not come up with an actually good way to bring up a thing I would just mention it anyway on the grounds that if it came up somehow later and I had not done so that would be weird."
Snort. "There might be some! It would probably be polite to explain, but..."
"I am not sure I would believe the outrageously powerful aliens who teleportation-assassinated the President if they claimed it was only because his alternate universe versions were sadistic psychopaths and he'd be hard to contain later."
"Oh, trust me, I'm not worried he didn't deserve it. But to mortal species 'a couple thousand years ago' might as well be forever and he hadn't done anything recently."
"Yeah. It'd make for an unusually accurate conspiracy theory if we explained, probably no more than that."
"And it wouldn't really serve to reassure the public - I'll send a couple people to keep an eye out for the place falling apart but only a couple, we're going to be really busy cataloguing and priority-ranking all Edda's new neighbors -"
"I have cultivated some of the frost giants to the point where I'd be reasonably confident in having them do stuff, although they'll be conspicuous anywhere..."
"I mean, Elves are only particularly advantaged among humanoids, that's only about eighty percent of the new places, if you'd like to send frost giants to the other ones they'd be much appreciated. It's kind of frustrating to be capable of killing gods and still hard-pressed to keep children from starving."
"Yeah. I'd like them to be supplementary at first before they're soloing new places, does that still help -"
"I mean, even if training them takes up as much time as the work they're doing, we're going to want to train them at some point and 'fifty new dimensions with three hundred new worlds to map' is as good an occasion as any for that."
They get to work. The planet whose president they just assassinated carries out an earnest and thorough and scrupulous investigation which turns up absolutely nothing.
And three days after that if Sibyl checks what will happen to her in the next hour what will happen is one of the Elves monitoring them appears in front of Sibyl without knocking and says "thesungoteatenbygiantspiders'.
She doesn't wait for them to check; she has to drop the precognition to alert the network.
There's this planet, where they seem to be chilling at home; there is unidentifiable vacuum unless he zooms out way far and then there's stuff -
"And they can teleport. Fantastic. Anyone have teleporting sun-eating giant spider containment strategies or do we need to find and tag every single one of them -"
"Are these the same thing as Ungoliant? What usually happens to Ungoliant?"
"As far as we could tell she settled down, spawned lots of baby spiders, and then starved to death in the forest - but that's when they can't teleport -"