Tracking down people who could use magic was a tricky proposition, but the siblings each had things they could bring to the table. Neither of them would have trouble noticing if someone used magic nearby, assuming no attempt was made to conceal it. They were looking for either captured wizards or enemy spies, and the methods used to find them would be quite different.
Douglas couldn’t think of an easy way to do the former, but for the latter he thought about how he would find himself. He could look for active magic or… a spellbook? It turned out to be fairly easy to make a spell that detected magical runes nearby. That immediately brought Douglas down a new path where he had to enchant his own spellbook with concealment magic. He helped Lucy work on a version of that spell for her own spellbook, and then wove it into his staff as well. Douglas was quite worried about the realization, and couldn’t help but keep talking to Lucy about it. If all it took was a simple piece of magic to find a spellbook, were even their notes safe?
“I wouldn’t worry about that…” Lucy shook her head, “I wouldn’t exactly say this is a simple spell. It searches out each and every rune after all. I doubt most people would think of it… and even if they did, it would take them more than a week to put it together. Besides, the range isn’t that long, right?”
Douglas shrugged. It could reach a block or two, which meant it would only be a few days at most to search a city… assuming the magic could be kept up all day. At the moment he would find it a much larger task. Douglas explained his thoughts, then gestured to Lucy.
“My work? Well, actually, it wasn’t that hard to come up with the basic form. See, the fey often search for human partners… too much magic in the blood has its problems. Well, the problem is active magical practice. Unfortunately they didn’t really write things down since they don’t forget magic after using it… and I didn’t really have any reason to learn it anyway.” Lucy waved her hand, “Anyway, since I knew it could be done it wasn’t hard to come up with the basic form and then write it down. You felt me use it the other day, right?” Douglas nodded. “I can’t guarantee how well it would work, but you can help me test the range. Though… I’m not sure if the amount of practice makes any difference. You probably have a bit more lingering magic around you.” Douglas looked down at himself then moved as if to brush himself off. “Don’t worry, I doubt anyone would be able to notice easily… you’d notice them using a spell like this first, at least. Are you worried about people from the Endless Library?”
Douglas shrugged, then explained, using a mix of his sign language and writing down words that weren’t in his repertoire. “They shouldn’t be looking for me, and here I’m not afraid of most of them. But setting up more active magic to hide using magic seems… counterproductive.” Douglas shook his head slowly.
“Maybe you can just brush off lingering traces of magic. We could test that. We’re mostly looking for those who have some magical potential but don’t know much yet… just enough to get noticed.” Lucy sighed, “The countess has people looking into rumors about those who can use magic, but she can’t verify herself… and she also wouldn’t be able to find those just moving through her county.” Lucy paused, “So what do you think about the countess? Should we be doing this?”
“You know what I think already. She treated me well before. She treats all those who work for her well. What, do you want to look for secret dungeons where she’s torturing people?”
“… Do you have a way to do that?”
Douglas tilted his head, then smiled. He started by holding up two fingers. “In a couple days, I’ll have a spell for it. Well, general secret areas.”
Douglas felt a very tiny bit bad for using time he was getting paid by the countess to develop magic for snooping into her business. However, they didn’t need to show results immediately and they had expected to take longer coming up with methods to find who they were looking for anyway. If they found something wrong with the countess… they’d figure something out. If there wasn’t, well, Douglas actually supposed having a spell for finding secret doors was actually useful for their primary task anyway. If there were kidnapped people, they might be kept somewhere hidden.
It was a bit of a tricky spell to nail down. The problem was by its very nature that it had to penetrate through walls, which were the bane of any detection spell. Any distance travelled through an object was a significant increase in difficulty for magic. On the other hand… the very thing they were looking for would make the job easier. If there was a secret door, there must be some path to it… slight cracks or the like. Likewise, the walls or floor in the area were likely to be thinner. Douglas started with a spell that could detect people through doors. Even though flattening the magic to slip under the door was more difficult than trying to move it in a straight line, a handful of centimeters of wood was a pretty sturdy barrier. Basically, it took more technique and less power to go around and under the door- but they weren’t exactly flush with the floor. Going around behind the hinges with the door closed was much more difficult… Douglas imagined it like tiny threads or perhaps a sheet of magic wriggling its way through.
At first the spell had seemed like a good way of searching for enemies. As a base, it made Douglas aware of the major features of a room- large empty spaces and big shapes. He could sense desks or even books, but he would have trouble counting the number of books on a bookshelf. People were pretty easy to notice, but the problem with detecting enemies with the spell was it took some time to spread out. Well, he supposed that if they weren’t in a hidden room but just behind a normal door it would be faster. Douglas didn’t actually expect to be attacked by anyone at the moment… but if they were tracking down magicnapped wizards, then those who had captured them certainly wouldn’t be his friends.
Before he could finish perfecting his spell, Lucy found something suspicious. She had been moving around the city testing her spell, and found traces of someone with magical ability in a wagon. She had followed it to a warehouse that the wagon went inside. Unfortunately there were many people around so she hadn’t felt safe trying to invisibly follow them inside. There wasn’t necessarily anything wrong- those who could use magic weren’t required to identify themselves and they were allowed to enter warehouses… but it was the sort of thing they were supposed to look into. While Countess Irieby could storm the warehouse with her soldiers, she wouldn’t do so without good reason. After all, if it was just a wizard who wanted to go about their business, she didn’t want to become enemies with them. Douglas supposed he would have a good excuse to test his spell… though he somewhat regretted putting off adding the components that would make the spell harder to detect.