"Figure out how to do a merfolk heist."

"Sounds fun."

"Depends on what they take. And there's a time limit."

"So that makes prep really important... The selkies don't really like students poking around their village, though, I don't think, so I'm not sure 'scout' is a viable plan."

"Yeah. I got a book on merfolk in general, but there weren't many details."

"I don't think anyone knows much... There might be something on inhabitants of the Lake in one of the books about Hogwarts, though."

"Guess I'll check again."

"I can skim through some too."

"That'll help."

Hug.

It takes her a little bit, but she reports back to Ellie with a list of inhabitants of the lake - "There's not much more on the selkies, except that these specifically are friendly to Hogwarts. They've tamed Grindylows though and use them like guard dogs, so those're a threat - the other animals they've got domesticated aren't really dangerous. There's also some other creatures in the lake, and apparently no one's actually sure everything that's in it... The squid's the biggest one but it's friendly."

"Big issues with grindylows is they'll swarm people and grab onto them - there's charms that can force them to release their grip, though, and they get startled by Animagus shifts it sounds like."

"And divers actually use muggle diving suits a lot, apparently, since those don't interact with magical plants, but the older methods and traditionalists were mostly stuff like gillyweed or potions made from it, the Bubble-Head Charm, self transfiguration, a healing spell that reverses suffocation damage, and some other potions for breathing underwater or holding your breath."

"Gillyweed's powerful, but might be too much - it gives you gills and adapts you to water, but then you can't breathe on land, and it takes over an hour to wear off even if you eat very little. The potions made from it are easier to control and some of the newer ones have antidotes, but they can be hard to make properly. Gillyweed also only grows in the Mediterranean, so we'd need to special order it. There's potions native to British witchcraft that don't work as long, but do cold adaptation, hearing, and seeing in the dark better, and Professor Sprout said that people diving in more northern waters sometimes set up like a straw system so they can slowly sip at the potion. I'm not sure how gillyweed interacts with the Animagus transformation... Though I think in general shifting forms breaks others transfigurations? Which you could use to end the gillyweed early, maybe, but then you couldn't use your different forms underwater."

"Self transfiguration is hard to do properly, since fish are really far from mammals, and dangerous if you mess it up, but you'd have to transfigure yourself a lot more to get like a dolphin or whale's lung capacity. Same with just healing yourself as you're running out of air, especially since people tend to panic when suffocating."

"The Bubble-Head Charm is usually a NEWT level Charms spell, but it runs until you cancel it. It makes a bubble that provides you with fresh air. It won't make the water feel less cold or make you better at swimming, though, but I think it should work no matter what shape you're in."

"So there's six weeks to the task. I can owl order the gillyweed now, that should be enough time to get it, and start learning the Bubble-Head Charm and maybe some extras, like warming charms, and then the gillyweed can be a backup plan. Figure on using the Animagus to scare the Grindylows to get me space to hex them, or just hex them straight off if I'm on gillyweed and not maintaining other spells."

"Sounds smart, yeah."

"Time to go ask Professor Reynolds about the NEWT-level Charms curriculum."

"We'll be ready to pass our NEWTs by fifth year at this rate..."

"The courses are designed for average students, which we are decidedly not."

"I love Hogwarts, but... Yeah, graduating early would actually be nice. Or at least convincing the teachers to let us into NEWT courses early - maybe we could sit our OWLs this year, actually... Even if they won't let us graduate at sixteen, we could do different NEWTs in seventh year. We'd end up more broad than specialized, but a lot of magic builds on other fields."

"It's kind of silly to start specializing that early, anyway. Wizards live forever."

"An excellent point. And we're gonna live literally forever, not just a century and a half."

"Yes!"

"Do it properly, too. No stupid magic fascism involved."

"Yeah, that's just unnecessary."

Giggle. "We'll probably have to invent our own method, but - we're smart. We've got time."

"If there was already a good one people would be using it."

"Yeah. There's long lived wizards, but most die eventually - so their immortality's clearly not perfect."

"We'll fix it."