"Yeah, that's fair," he agrees. "In which case I guess the first problem to be solved is getting you a cutting of that tree?"
"Yeah. The problem with gates is that they can take any amount of time to settle. Days, sometimes. And they start open. If I make one, and it settles while I'm asleep, there will just be an open Fairyland gate to right where he'd be looking for me if he looked."
"...That's... potentially solvable," he says thoughtfully. "And, um. I feel like I owe you an explanation of why I'm so interested in solving your problems - I mean, I'm sure you've guessed that I'm very excited about potentially learning sorcery, and it may be apparent that I'm of a problem-solving nature in general, but there's cultural context on top of that."
"It's... I might make a mess of this, I apologize, I'm using up a lot of brainpower on name-related censoring and trying to avoid saying things that might be orders, but - the word 'vassal', on this planet, refers to a cultural phenomenon with no magical enforcement whatsoever. And under that system, having a vassal comes with responsibilities. I take those responsibilities very seriously. You're obviously coming from a vastly different context, but as far as I'm concerned, for as long as you are magically required to obey my commands I have a personal duty to see to your safety and comfort."
"I know, but I'm being paranoid about it anyway because my level of discomfort with this entire system is extremely high."
"Oh. Set up the gate in an uninhabited location that would be prohibitively difficult to leave unassisted, and monitor it remotely in case anybody comes through. Then if we get any unexpected visitors they're alone on a deserted moon with no idea where you are. And you can check it at your leisure with your handy access to mortal technology. It'd be a little expensive to do it that way, but if you verify that the interplanetary portals are possible and express an interest in making some eventually, I, um, happen to be childhood friends with the emperor of this planet and could probably get him to front some extravagant aid if it means you start with us when you do get around to selling portals."
"I guess I should check my assumptions. How high can fairies fly, and what if anything stops them from going higher?"
"If we go up too far the air gets too thin for wingbeats to do anything. I'm not sure if anything would stop the ones who can teleport. I guess they might pass out eventually."
"Crystalswifts. They don't go very far, but they could probably outpace falling speed if they tried."
"That sounds like a deeply inefficient method of space travel," he says. "If there aren't any precise long-distance teleporters, sticking the gate on a moon will almost certainly work just fine. Space is big."
"The solar system one actually shrank the distances between planets by a lot, proportional to their size," he says. "Because when the scales are accurate it can be difficult to have more than one planet in view at a time, even in the same system, the littler ones would be the size of dust motes before you could fit them all in a display area together. Space is big."
"Okay. Then if we decide on a solution to the tree thing that requires lots of money, I can politely ask the Emperor for lots of money, and he'll want to see proof that you exist and can do magic of the relevant type, but I'm pretty sure he'll come through once that's established."
"Okay. ...It probably is safe just to wait a while until he won't be likely to have the tree staked out and then do a tiny gate, though. Especially if someone can keep poking a stick through the area to check if it's open all the time. I could also maybe just make the gate to the inside of my tree, I think with a little finagling I could get it to extend a plantable branch through the inside. Nobody can get into my tree if I don't let them and he never made me let him."
"That seems simpler all round," says Silver. "What do gates look like? How frequently and how consistently would you want it being poked with a stick to ensure that you caught it soon enough after it opened?"
"If you want an invisible portal poked with a stick every minute or two for possibly days at a stretch, I might have to ask someone for help," he says. "But it's doable."
"I don't know that he'll be staking out the tree. If anyone saw me go through the tear, they won't expect me back, and I don't think he wanted to keep me particularly badly. But if he was it would be important to be able to react quickly."
"Yes," he says. "I see the logic. So, you could try to make the gate to the inside of your tree - would that be a secure enough method that you wouldn't want it poked with a stick at all hours?"