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Chapter Ten—A Real Education

"And you're sure that your new duties won't interfere with Severus's education?" Mariana watched Harry closely as he showed Severus how to sprinkle chopped bay leaves into the cauldron so that the Somnium Draught, a mild version of the Dreamless Sleep potion, would come out perfectly.

"I'm sure, Mrs. Prince." Although Mariana had granted Harry permission to call her by her first name, and certainly called him by his, he had been more formal lately. Maybe it was Black's influence. Harry shook his head, moving his longer fringe out of his eyes, and smiled at her. "Severus always comes first."

"I have to come first," Severus said. "I was here first." He paused and looked closer. "Why is the surface shimmering like that?"

Mariana felt her eyes widen, but before she could say something, Harry curled his arm around Severus's waist and tugged him off the stool he was standing on to reach the table where the cauldron sat. Mariana herself stepped nimbly out of the way as they watched the cauldron settle back into place with a rattle.

"That was less explosive than—"

A silent column of purple potion rose out of the cauldron. Harry's wand flicked, containing it so that it fell as a column back into the cauldron, rather than splattering all over everything. Harry sighed and shook his head. "Maybe I should leave his training in brewing to you, Mrs. Prince. I'm not as good at it as you are."

"Why did it shimmer like that?" Severus demanded, wriggling in Harry's grip. He turned around and gave him a stern look.

"We did something wrong."

"Yes, but what?"

Harry gave Mariana a helpless glance, and she smiled a little and took over the explanation. "You must not have added enough powdered lapis lazuli, Severus. That would mean the potion was unstable when the bay leaves were added, and it wouldn't take very much of them to cause an explosion."

"What makes the lapis lazuli react badly with the bay leaves?"

Mariana settled down in the nearest chair to explain the concept, while Harry silently cleaned up the cauldron. Mariana kept an eye on him. She didn't care for the dark look his face wore when he was silent, and she also knew that, although he wasn't as skilled at brewing as most Princes were, the mistake he had made today wasn't one common to him. He had reacted quickly enough to spare Severus any harm, of course, but…

Something was wrong.

"Mr. Evanson, thank you for agreeing to come."

Harry gave a short nod to Orion Black and looked around the playroom that he'd been ushered into, after being guided from the door by a shivering, terrified house-elf. There were small bookshelves around the walls, and the ceiling had been done in a constantly shifting constellation of stars that would show several different parts of the night sky. There were rolls of parchment, quills, and what looked like soft plush numbers on several small tables, accompanied by chairs of the right size for children.

"I don't know much about teaching children their letters and numbers," Harry thought he had to mention. "I thought I was going to be teaching Sirius and Regulus about magic."

Black stepped up behind him, and Harry fought to keep his back from stiffening. "Of course," Black said softly, and for a second, his fingers trailed down Harry's shoulder. "These are here so that I can pick up on lessons with my sons when you've finished."

Harry twisted around to gape at Black. "You're going to teach them?"

"Did you not think I could?"

"Well, no, or you wouldn't have left them to tutors in the first place."

For a moment, Black stared at him. Then he said, "I trusted my wife to find the tutors, and I trusted her to take care of them. Will you blame me for trusting her?"

Harry only shrugged, not wanting to say what he thought in front of Sirius and Regulus, who were walking into the room. Regulus immediately went and sat down in one of the little chairs, but Sirius flopped down on his belly in front of his and watched Harry. Harry snorted. He recognized a test of his authority when he saw one, even if Sirius wasn't as annoying as Zacharias Smith had been when he questioned Harry in front of the DA in fifth year.

"You can lie on the floor if you want," he told Sirius. "But then you won't be able to move the practice wand I brought you all that well." Laocoon had started selling practice wands that were capable of channeling innate magic in some pale imitations of spells last year, and he hadn't objected at all to Harry bringing them along. In fact, he was probably making plans right now to tell everyone who came into the shop about the Blacks patronizing it.

"You do blame me," Black said behind him, even as Sirius popped up and declared, "Wands?"

"Wands," Harry agreed, and pulled the practice sticks out of the plain black satchel he was carrying over his shoulder. They were both made of rowan, a precaution that Laocoon had taken on his own but Harry thought sensible. That wood would make it harder for his little students to accidentally hurt each other or cast Dark spells.

"I insist on speaking to you, Mr. Evanson."

Harry didn't miss the wary way Sirius looked at his father, or Regulus cowered back as if to hide his face. Harry turned around and gave his own look in Black's direction. "Pardon me, Mr. Black," he said, enunciating every word the way he imagined a snotty pure-blood would, in case that made it more comprehensible for Black. "But you're interrupting the lesson."

Black stood as still as if he was going to strike. Harry watched him. He hadn't thought the man would attack him in front of his sons, but then, Black had already proven more bigoted and bullheaded than Harry had thought.

A second later, he turned and stormed out of the room. Harry rolled his eyes, but made sure he was done with the gesture before he turned back to Sirius and Regulus. "There, he'll have some things to think about," he said cheerfully. "Would you like to learn how to practice magic?"

"We're little," Sirius whispered. He was staring around as though he thought his father was going to pop out from behind a chair.

"I know," Harry said. "Which is why you can just watch me for right now." He laid the practice wands down on the little table and grinned at Sirius. "Are you going to get up so you can use the wand, or just lie on your stomach all day?"

"I could do some from here," Sirius protested, but he did get up and walk over to sit on the little chair next to Regulus's, his eyes bright with something Harry at least hoped was curiosity.

"Sure, you could," Harry said, and got a wondering smile from Sirius. His heart ached as he thought of the man who had been his godfather in his own world, but, well, that was gone now, and through his own actions. The least he could do was try to make sure that this Sirius and Regulus had better futures than the past he had given them. "Look what happens when I move my wand like this."

The Elder Wand hummed in his hand as if objecting to being used as a demonstration for children. Harry ignored that. It had replaced his holly wand, which meant it was going to have to put up with things it didn't like.

He swept it slowly through the air in front of him, making the motion big and obvious. Sparks trailed him and danced down to rest on the carpet in front of Sirius and Regulus. Sirius's eyes went big. Regulus let out a yell and then clasped his hand over his mouth.

"You okay?" Harry asked gently, crouching down in front of them and keeping the Elder Wand out of the way.

"Fire," Regulus whispered, but his eyebrows went up and his brow furrowed when he realized that the sparks didn't seem to have caught. He glanced sideways at Harry.

"There are spells in here that will prevent anything bad from happening with your magic," Harry said reassuringly. And that was true; he'd felt the spells the moment he'd stepped into the nursery, far more part of the walls and floor than the shelves or any of the other furniture. "I'll go slow and show you lots of simple magic, though, okay?"

Regulus nodded even though Harry wasn't sure how much he'd understood. He stood back up, and Sirius waved his hand around wildly.

Harry smiled. He decided that one of the tutors had probably enforced the same rules about raising hands that Hogwarts professors would have. "What's on your mind, Sirius?"

"We can't do magic because we're little," Sirius said with authority.

"I think you'll find that you can," Harry murmured. He had chosen this particular lesson because it didn't involve an actual spell, but hopefully it would still sneak past the ideas the boys might have had put into their heads about how they couldn't do any magic at this young an age and show them their power. "It's not the same as the spells your Dad does, right?"

Sirius slowly shook his head. "Or our Mum," he whispered, then flinched.

Regulus tensed up in his chair. Harry reacted without thinking through whether it was the right thing, just scooping Regulus out of the chair and putting him on his hip. Sirius stared with his mouth open.

"That's like our Dad!"

"Yes," Harry said. "I promise, I'm not here to hurt you. I'm here to help you. Do you want me to show you the thing with the wand again?" He looked back and forth between Sirius and Regulus for a second, then reckoned he wouldn't get an answer until he put Regulus down. He plopped him back in the chair and ruffled Regulus's hair with his fingers.

Regulus blinked at him, so adorable that Harry had to grin. He turned to Sirius.

Sirius seemed to realize he had to be the decision-maker, if Regulus even understood what was going on. Black had said that Regulus didn't speak much but did understand. Sirius took a deep breath and squared his shoulders. "Show us the thing with the wand again."

Harry grinned in delight and stood. He was more than happy that the boys were getting past whatever barriers their mother and their tutors had put in their way. He didn't need to be addressed formally, even if it was cute when Severus did it. He just needed to be able to teach them.

"Watch, then," he said, and trailed the wand slowly through the air again. He wondered if it was his imagination that the Elder Wand didn't thrum in indignation this time, or not.

Albus sighed and raised his head slowly from the crystal bowl of pure water he had gathered. Gellert was waiting for him with a cloth to wipe his face and an impatient expression. Albus shook his head.

"I don't understand how one man is able to hide from us this easily," Gellert said, in the kind of low voice that might sound charming from a distance but that Albus knew could break into shouting all too easily.

Albus dried his face and said nothing. Neither of them had that much talent in scrying, or this would have been much easier. And Izzy hadn't given them more clues, even a length of time that history had changed in, which would have made it easier to narrow the hunt.

"There's no one obviously out of place," Albus said at last, when Gellert had taken the chair closest to the fire and been staring moodily into the fireplace for several minutes. "Of course, enough time has passed by now that he could have been able to adapt to the world around us."

"Tell me something I don't know, Albus."

"He's an oddly modest time traveler. He hasn't tried to claim a prominent place."

"How do we know that, though?" Gellert tossed his head back, crushing a wave of pale curls against the back of the chair. "The timeline has changed enough to make us think that someone who is new might always have been here."

Albus paused and then sighed. "You're right, of course. It's so hard to understand what happened, what changed, and what we should do when we catch up with him."

"Shake his hand. You would have put me in prison, Albus."

"Well, I doubt that you surrendered in the other timeline the way you did in this one."

Gellert turned his head and frowned. "If you were a professor at Hogwarts, why do you think you would have been involved in the decisions to make me surrender and put me in prison at all? That's a rather odd detail in Izzy's story."

Albus sat down in the chair beside him and closed his eyes. "Does that mean that you don't believe it?"

"No," Gellert said after a long, silent moment that ground on Albus's nerves like the gears of a clock pressing against each other. "No, I know that it's real." He sighed and shook his head. "It's ridiculous, but I believe it. And it doesn't get us any closer to tracking our time traveler to disbelieve it."

Izzy appeared with a crack in front of them before Albus could say anything. She stared at the crystal bowl with water in it and then turned and stared at them. "Mr. Albus and Mr. Gellert is being civilized and cleaning up," she said.

Albus blinked for a minute, wondering what she meant, and then realized that he had dripped water down the side of the chair. He nodded. "We will, Izzy, I promise. I'm just a bit exhausted from the scrying and need to rest for a moment."

Izzy rolled her eyes and snapped her fingers. The bowl and the water vanished, and two mugs of hot tea, from the scent, appeared in front of her. "Izzy can be helping Mr. Albus and Mr. Gellert this once," she said. She paused as she watched them pick up the mugs and then twitched her ears. "Or maybe twice."

"You can do something to help us find this time traveler?" Albus asked, trying not to be too hopeful. It sounded like that might be what she meant, but he didn't actually know.

"Izzy is helping in her own way." Izzy folded her arms and studied them. "And only because both of you be messing up if you be trying it." She held out her hands, and something formed in the air above her palms, so bright that Albus shielded his eyes with the side of his mug.

"No," Gellert breathed.

"No, what?" Albus shot him a curious glance, even as he felt the Elder Wand thrum in its holster at his side. It had been acting strangely lately, sometimes feeling inert and sometimes bursting with power, but he didn't remember it reacting like this.

"I—I searched for one of those, for years. It would have been the ultimate weapon against a large army. And I could have just turned to a house-elf and asked for one?"

"Most house-elves not be giving you something like this, Mr. Gellert. I only be doing it because others agree."

Albus finally managed to see what was going on, although the center of the silver thing hovering over Izzy was still too brilliant to look at. It resembled a four-pointed metal star, with a spark like a diamond embedded in each point. Albus shook his head. "I have to admit that I don't know what I'm looking at, even though I should if you wanted it for the war, Gellert."

"It's…" Gellert cleared his throat. "It's a weapon called the Expiscor."

"It finds something?" Albus asked. His Latin was a bit rusty.

"It finds someone," Gellert corrected, his voice hushed. He had leaned forwards as if to take the Expiscor from Izzy, but she shifted and stared at him, and he ended up sitting back in his chair. "The most dangerous and powerful enemy you have. It kills them. It can fly and slice through…" He trailed off, this time because Albus was fairly sure his expression mirrored Izzy's. "Well. Yes. It kills that person, and then it locks onto the next most powerful and dangerous enemy you have, and kills them. It can't be hurt. It can't be broken. It can be blocked, but it takes a lot of power, and probably the only person who could summon that kind of shield is the Expiscor's first target."

"And it won't hurt the time traveler that we're looking for?" Albus asked. He might not have decided if he owed this time traveler a debt or not, but he certainly wanted him alive.

"This be the original design," Izzy said, an undertone of grave sadness in her voice. "Not the twisted weapon humans be making." She drew her hands back, and the Expiscor kept on hovering. "It find only. It be drawn to power."

"Can we be sure that it's going to find the time traveler and not Albus, then?" Gellert's voice was a bit more subdued than usual, but only a little. Albus refrained from rolling his eyes, then decided he might as well.

Izzy gave them both a strange look, but it was a long moment before she spoke. "This man be being more powerful than Mr. Albus."

Gellert drew in his breath with a long hiss. Albus looked at him. "You're married, remember."

"I wasn't—for the love of Merlin, Albus, now is not the time to joke!"

"You always think it is," Albus muttered, and returned his attention to Izzy. "The Expiscor will lead us to him?"

Izzy nodded. "But it be needing some time to draw on the magic of this changed world and grow used to it. I last be calling it in the world as it was. Follow it tomorrow, Mr. Albus." She disappeared with a sudden pop.

"I should never have ignored house-elves," Gellert pronounced solemnly.

"You should never have ignored any of the ones you thought were weak and helpless."

Gellert thought about it, then said, "No. I think it's only house-elves."

Albus sighed and went to eat the meal that had been waiting under Warming Charms since before he started to scry, trying to ignore the fact that he had one of the most powerful weapons in the world hovering in the middle of his drawing room.

And the longing looks that Gellert kept giving it.