The incident with the Devil's Snare was the end of Merula's period of inactivity. Not a day passed without Merula either taunting Grace or stealing her things and hiding them around the common room so that Grace was late to class. When Slughorn wasn't looking, she tripped Grace and caused her to smash her potion, or threw excess amounts of an ingredient into her cauldron and ruined her hard work.

Rowan had given her a plant in a painted clay pot for Christmas. Grace had just left the dormitory one morning when she heard the sound of something smashing against the floor. She turned and hurried back into the dormitory.

Merula smirked. "Oops."

Grace's hands shook and she automatically reached for her wand. It took every ounce of her self control to turn and walk away instead of hexing Merula.

Grace, Rowan, and Ben had taken to eating in the Artefact Room to avoid Merula. Grace spent all of breakfast that day ranting about Merula's latest antics. As soon as she finished eating, Rowan left the Artefact Room and went in search of Merula.

She entered the Great Hall and walked over to the Slytherin table. There was no sign of Merula, but hopefully one of the others would know where she was.

The first-years were discussing something as she walked over, and she wasn't sure how to interrupt their conversation. She waited awkwardly, listening to the conversation going on at he table. Sam, as usual, hadn't joined the conversation, choosing to sit in silence, though Rowan had a feeling that he heard everything that was said around him. Ethan, Liz, and Barnaby were debating something that had to do with the relationship between the number of Bowtruckles that lived in a tree and the quality of the wood it produced. Ismelda, she noticed, was also missing. Rowan wondered if she was with Merula.

"The Bowtruckles help the tree by eating wood lice, which would otherwise lower the quality of the wood," Liz insisted. "It's only because of the Bowtruckles that the wood is such high quality." She was surprisingly animated; normally, she was almost as quiet as Sam, only joining the conversation when invited.

"But Bowtruckles are picky about their homes, so naturally they would gravitate towards trees of a higher quality," Ethan argued.

He caught sight of Rowan hovering near the table. "Rowan! Settle a disagreement for us; do Bowtruckles raise the wood quality of the trees they live in, or are they naturally attracted to trees of a higher quality?"

"Liz is correct," Rowan said. "When bowtruckles live in a tree, they imbue it with their own magic, strengthening the tree." The relationship between a bowtruckle and it's home was a fascinating one; bowtruckles were born with very strong magic. When they became fully grown, they chose a tree to live in and transferred all of their magic to it. Without a nearby source of magic, bowtruckles became sick and died. This was why moving bowtruckles to a new home was so difficult, and why cutting down magical trees was forbidden without first taking care to rehome the bowtruckles it housed. "But, um, that's not why I came here," she said, stumbling over her words. She wished Grace had come with her. Rowan hated talking to others. "I was wondering if you knew where... I'm looking for Merula, and I thought you might..." She gave up and let her sentence trail off, hoping the Slytherins would be able to make sense of the vague fragments she had uttered.

"She and Ismelda went to the Quidditch pitch," Ethan said.

"What are they doing there? They didn't... steal some of the school brooms, did they?" Rowan asked in disbelief.

"I don't know. They didn't say," Ethan said with a shrug. Rowan left the conversation there and walked to the Quidditch pitch.

As she neared the Quidditch pitch, her eyes picked out two figures on brooms flying high in the air. Clearly Merula and Ismelda had stolen the school brooms. They were throwing something red back and forth.

Rowan climbed the stands. "Merula! I need to talk to you!" she yelled.

Merula caught the Quaffle that she and Ismelda had been tossing back and forth- Rowan wondered if they had stolen that as well. "What?" she snapped, looking at Rowan with an annoyed expression.

"Leave Grace alone," Rowan shouted.

Merula flew closer. "No."

"What do you have against her?"

"She's a disgrace to Slytherin, and she ruins the life of everyone she associates with," Merula said.

"Grace hasn't ruined anyone's life," Rowan protested.

There was bitterness etched into Merula's face. "You don't understand what it's like to be a Slytherin, to have the whole school judging you, wondering when you'll prove yourself to be evil. Prickle doesn't understand either. She's convinced we can win over the other houses just by playing nice, but we can't! All she's doing is giving our yearmates false hope and setting them up for failure. We will never be forgiven for our parents' mistakes!" Merula's voice rose to a shout. She broke off, staring at Rowan, her chest heaving, looking startled by how much she'd said.

"Grace is only trying to help! You can't blame her for-"

Leave, Khanna," Merula cut her off.

"No," Rowan said.

Merula narrowed her eyes. "Excuse me?"

"I'm not leaving. There must be something I can get you to do to see reason," Rowan said. She stared stubbornly at Merula, willing herself to not look away.

"Fine. Ismelda!" Merula called. Ismelda flew over. Rowan was certain she'd been listening to their conversation, but she showed none of her thoughts, simply looking bored. "Give Khanna your broom."

Ismelda flew into the stands and got off her broom, silently holding it out to Rowan. She took it, not sure what she was expected to do.

"Get on. We're racing," Merula said curtly.

Rowan climbed onto the broom. She could feel herself trembling. She wasn't the best at flying, and the idea of racing unsupervised scared her.

"Once around the Quidditch pitch. If you win, I leave Prickle alone," Merula explained. Suddenly, she leaned forward and started flying.

Taken by surprise, Rowan sped forward. The gap between her and Merula shrank until they were side by side. The wind whipped through her hair. The speed they were flying at terrified her.

Merula looked at her as she flew alongside her. Abruptly, she jerked to the side, slamming into Rowan. Rowan clung desperately to her broom, struggling to not fall off.

I've had enough of this, she thought, diving towards the grassy field. Her palms were sweating and she didn't want to fall from so high up.

Merula followed her down. As Rowan leveled off at the bottom of her dive, Merula slammed into her again. Rowan's hands slipped off the broom and she fell onto the grass. Fortunately, she was low enough that nothing was injured except her pride.

Merula completed her lap around the pitch before flying back to Rowan. "I won," she said with a defiant expression.

"You cheated!" Rowan exclaimed. She was shaking as she thought of what had almost happened. Merula could have killed her if she'd knocked her off before she'd dived.

"For a Ravenclaw, you're awfully dumb. I was never going to let you win, Khanna. I can't leave Prickle alone until she understands that this is what Slytherins do. We don't protect others, we don't play fair, and we definitely don't make friends," Merula said.

"There must be some way to convince you," Rowan said. She had told Grace to let her work things out, and she wasn't leaving until she'd done her job.

Merula pulled out her wand. "Flipendo."

The jinx knocked Rowan off her feet. For the second time in five minutes, she fell onto the grass.

"I already warned you once, Khanna. Leave," Merula snarled.

With a heavy heart, Rowan turned and walked away, accepting that she'd failed.

"Flipendo."

Rowan fell forward. She turned and glared at Merula. "What was that for?!"

Merula smirked. "I told you, Slytherins don't play fair."

A week later, Rowan and Grace met in the Artefact Room. On Rowan's lap was a thick book of dueling spells that she'd checked out from the library.

"There are two spells that I think you should try to learn," she said in a brisk voice. "The first one is Expelliarmus. It will disarm your opponent, and the book says it's an essential spell for anyone learning to duel."

Grace nodded. "And the second spell?"

Rowan flipped farther back into the book. "This one's quite a bit harder. We won't learn it in class until next year, but I think you're good enough at Charms to cast it with a bit of practice. Besides, a lot of early spells are designed to give your opponent minor cuts and bruises, and while they don't cause serious injury, you want to avoid hurting Merula at all if possible."

"Are you going to tell me what the spell is?" Grace interrupted.

"Rictusempra, the Tickling Charm," Rowan said.

"You... want me to tickle Merula," Grace repeated slowly.

"She can't cast spells if she's laughing uncontrollably. And she'll never expect it, it's a lot more advanced than anything we've used in class," Rowan said defensively. She turned the book around and showed Grace a picture of someone doubled over, clutching their sides as they laughed.

"All right. Thanks, Rowan. I'll start practicing those spells today," Grace said.

Rowan marked the pages for her before handing over the book. "I talked to Ben, and I think I've found a place for you to practice."

"Where?" Grace asked.

"The Room of Requirement. It's on the third floor, opposite the tapestry of the dancing trolls- you remember where that is?"

Grace nodded. "But, Rowan, there's nothing there except for a wall."

"That's what I thought until Ben showed me how to get in. You have to pace back and forth and think about what you need from the room," Rowan explained. "Come on, I'll show you."

"How did Ben find this room?" Grace asked as they walked.

"It appeared when he needed a place to hide from those two boys who were bullying him," Rowan said.

She stopped and gestured dramatically to a blank section of the wall. "I present to you... the Room of Requirement."

Grace paced back and forth in front of the section of the wall that Rowan had indicated. I need a place to duel, she repeated over and over.

Rowan gasped. Grace opened her eyes and looked at the wall, where a plain wooden door had appeared. She pushed it open. Beyond the door was a large room with an open space in the middle. At one end of the room was a line of training dummies. There were also piles of cushions and shelves of books.

Rowan sat down and started working on an essay for Transfiguration while Grace practiced the spells. She started with Expelliarmus, since it was easier and she thought it would be more useful. Not that she didn't trust Rowan's choices, but how many times in her life was she going to need to tickle someone?

Each of the dummies was holding a wand. When Grace cast Expelliarmus successfully, the wand would jerk out of the dummy's hand and fall to the ground a few feet in front of it. According to the dueling book, the wand was supposed to fly all the way to her, but that would take more practice.

Finally, Rowan convinced her to stop practicing. "It's late. Let's get lunch, and then explore the castle a bit. There are still some rooms on the fifth floor that we haven't looked at," Rowan said, putting away her essay.

"I don't see why you're so excited. We know what will be in those rooms. Dust," Grace said. She didn't understand Rowan's fascination with the unused portion of Hogwarts. She would much rather be outside, even if the days were cold, than cooped up in some forgotten, dusty room.

Rowan gave her a pleading look. "Please? You might find something you like. There are all sorts of fascinating objects in these places."

"All right. Let's go," Grace said. She followed Rowan to the fifth floor. There were some classrooms on the fifth floor that were still used, but the majority of them were abandoned.

Rowan pushed open a door. The hinges squealed in protest. "Lumos," she said. Grace copied her, and the lights from their wands illuminated the room they had entered.

Immediately, Grace's interest piqued. The room they were in was an abandoned classroom, as expected, but there was something odd about it. There was a charge in the air, and she could feel the hairs on her arms standing on end.

She searched for the source of the energy, following a faint tugging sensation to a painting that was hung on the wall. A thick layer of dust all but obscured the painting, which appeared to be of a bowl of fruit.

Rowan approached the painting as well, her dark eyes filled equally with nervousness and excitement. Together, they pulled the painting off the wall to reveal a series of glowing blue runes carved into the stone behind it.

"Ancient runes!" Rowan gasped. "I wonder what they say..." She rummaged through her bookbag.

Grace wasn't listening. She felt an increasing pull towards the runes now that the painting was gone, and stretched her hand out towards them.

The moment she touched the runes, she felt a jolt of energy, as if she'd been dunked in freezing water, and then everything turned black.

She found herself in a white room. The air was cold and her breath formed clouds in front of her. "Where am I?" she asked the empty air.

There was a creaking sound behind her. She spun around, readying her wand. A large pile of snow-covered rocks shifted, growing taller. Chunks of snow fell from rusty armor. It wasn't a pile of rocks as she'd thought, if was a giant knight, almost as tall as Hagrid. Grace eyed the huge sword hanging at his side. The knight was slow, so hopefully she could outrun it. If only she knew where she was...

"Someone has called for my help again. I am needed," the knight muttered. He didn't seem to have heard Grace. "But where are they? Where are those I have sworn to protect? No one comes for sanctuary anymore."

With one last creak, the knight was standing upright in front of Grace. She realized that she could see the back of it's helmet; there was nothing inside the suit of armor.

"What's happened to the Muggleborns? Are they safe now?" the knight asked desperately.

Grace shook her head, confused. "Yes," she said hesitantly.

"Forever? They're safe forever?" the knight clarified.

Grace nodded, unable to speak. She was overwhelmed by the strange conversation.

The knight's shoulders sagged and Grace got the strange feeling that it was relieved. "Then you've come to lay me to rest," it said in a voice that sounded exhausted and strangely proud. It dropped to one knee and bowed its head. "Do it. Please."

Grace took a step back. "You want me to kill you?!"

"I am not truly alive, so I can't be killed," the knight said. "I need you to undo the enchantments keeping me as a semblance. But you should already know that. Unless..."

The knight staggered to its feet, attempting to draw its sword at the same time. That was one too many things for it to do at the same time, and it lost its balance and fell back to the slippery floor. Grace jumped back as the knight crashed to the ground. She lifted her wand, though she couldn't think of anything she could do to defend herself against an animated suit of armor.

The knight's second attempt at standing was more successful. It raised its sword and swung it through the air. Cold air rippled out from the tip of the sword. Green light came from the center of Grace's chest.

"You're one of Slytherin's," the knight snarled. "Where are the Muggleborns? What have you done with them?"

"I haven't done anything!" Grace protested. It felt like an invisible string was pulling her away from the strange room. The knight blurred.

"Hogwarts has fallen. I must defend the castle," the knight said. The last thing Grace saw before she was dragged away from the room was the knight touching its sword to an ornate set of doors. A massive snowflake sprouted from the center of the doors, blocking them off. The light reflecting off the snowflake grew brighter and brighter. Grace closed her eyes against the blinding white light.

Someone was shaking her shoulder and calling her name. When Grace opened her eyes, she saw Rowan looking down at her with a concerned expression.

"You're awake!" Rowan cheered. "I was so scared."

"What happened?" Grace asked. She stood up, waving away Rowan's helping hand. "I'm fine," she insisted.

"You collapsed after you touched the runes. You were rigid, and you felt as cold as ice. I was just about to go get Madam Pomfrey. How do you feel?" Rowan asked.

"I feel fine, just cold," Grace said.

Rowan relaxed a fraction. "You'd better go to the Hospital Wing anyway."

"I'm fine," Grace insisted. "Besides, I need to tell you what I saw."

That got Rowan's attention. Grace could see the emotions battling in her friend's eyes. On one hand, she was curious to hear what Grace had to say. On the other hand, she was worried about Grace's health.

"Meet me in the Room of Requirement. I'm going to get you some hot chocolate from the kitchens," Rowan finally said.

Grace didn't object. She was still freezing, and nothing sounded better at that moment than a nice hot drink. "I'll ask the room for a place to relax," she told Rowan.

Once Grace had persuaded Rowan that she wasn't going to faint on the way to the Room of Requirement, Rowan walked down to the dungeons, leaving Grace to enter the Room of Requirement.

She paced back and forth, thinking I need a place to relax. After a few repetitions, a door appeared. She opened it.

This version of the Room of Requirement was much different than the one she'd spent the morning learning to duel in. The floor was covered in soft green carpeting. One wall was filled with large windows that overlooked the Forbidden Forest. Next to the windows were two bean bag chairs and a stack of blankets. She sat down on one of the bean bag chairs and wrapped a thick blanket around herself.

A few minutes later, Rowan returned with two mugs of hot chocolate, as well as two sandwiches and an assortment of cookies. "The house elves were quite offended when I said all I wanted was a mug of hot chocolate. Besides, we missed lunch," she explained.

Grace wrapped her hands around ne of the mugs of hot chocolate. She sipped at it, allowing the warmth to chase the lingering cold from her body.

When she had warmed up, she realized that she was starving. She reached for one of the sandwiches Rowan had brought.

Rowan waited until she had finished eating to say anything, which Grace thought was impressive given her friend's powerful curiosity.

"So, what did you see?" Rowan asked impatiently, evidently deciding Grace had been given enough time to recover.

Grace described what had happened, how she'd touched the runes and been transported to the strange room with the knight. Rowan pressed her to remember every detail, writing everything down in a small notebook provided by the Room of Requirement.

A pensive look appeared on Rowan's face. "Do you think the chamber you saw him in was one of the Cursed Vaults?" she asked.

"It must be. How many hidden chambers can there be in the castle?" Grace said.

"Well, there's the Chamber of Secrets, and this room, though I'm not sure I would call it hidden. And in 1892, it was discovered that one of the professors had been performing illegal experiments with potions in a secret room under the dungeons. And I've heard rumors that-"

Grace laughed. "It was a rhetorical question."

Rowan deflated. "Oh."

Grace felt bad. She asked the room for a map of Hogwarts and a quill. The items appeared on the floor between them. "Actually, it would be helpful to know where in the castle strange things tend to happen."

Rowan's eyes brightened. She launched into a long lecture. Some of the rooms she described were said to have existed for hundreds of years, while others had been constructed more recently. Grace marked the rumored locations of the oldest rooms on the map, figuring that those would be the best places to start.

She folded the map neatly. "I'll send a copy of this to my parents," she said.

"We should return to the room where you had your vision. I want to try to translate those runes," Rowan said. "That is, if you feel up to it..."

Grace stood up. "Let's go," she said.

Rowan followed her out of the Room of Requirement and into the corridor. "You can read Ancient Runes?" Grace asked as they walked.

"Only a little. I started learning on the farm last year. It's lots of fun," Rowan explained.

They reached the room. Grace pushed open the door. The temperature in the room was several degrees colder than it had been a short time ago, and the electric tingle she had felt earlier was replaced by a painful prickling.

She walked over to the runes. They were no longer glowing.When she held her hand over the runes she could feel a force repelling her, as if she was trying to push the same ends of two magnets together.

Grace stepped aside and let Rowan look at the runes. Rowan scanned the short message. "The Ice Knight stands guard past the Vanished Stairs," she translated after a moment.

"That was fast," Grace said.

Rowan shrugged. "I have a good memory."

Grace was about to reply when she heard a familiar voice calling her name. "Grace."

She looked around. "Jacob?"

"Grace? Are you alright?" Rowan asked.

"Can't you hear him?"

"Grace. Can you hear me?"

"There he is again! Yes, I can hear you, Jacob!" she said excitedly.

"I don't hear anything," Rowan said. Grace ignored her.

"You have to be the one to find me. Follow the trail," Jacob continued.

"Jacob?" Grace asked, but there was no answer. "Jacob!"

She looked at Rowan. Her shoulders slumped. "He's gone."

"You heard your brother? What did he say?" Rowan asked.

"He said that I have to be the one to find him, and then he said that I need to 'follow the trail'," Grace said. "What do you think he meant?"

Rowan looked perplexed. "I have no idea."