Creature from the Black Lake Part 3

Introduction

Hello everyone, welcome to our Walkthrough section for the Creature from the Black Lake Part 3 of Harry Potter Hogwarts Mystery! You and your friends uncovered disturbing rumours about a creature lurking near the Black Lake. Messages in bottles appeared along the shore, some even mentioning Penny by name, raising fears that she could be in danger. You investigated the lakeshore, found mysterious footprints, and consulted with Hagrid, narrowing down the possibilities to a Merperson, a Kelpie, or a Kappa.

Despite your best efforts, the mystery deepened. Messages continued to surface, Hogwarts students were warned to stay away from the lake, and Merula Snyde went missing, showing that the threat might be far more serious than anyone anticipated. With the professors uncertain about the creature and no clear answers yet, you and your friends are left to continue the investigation, determined to uncover the truth and protect those at Hogwarts.

Summary

Walkthrough

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You’ll need to wait six hours before you can continue.

Head to Great Hall once the waiting time is over. You’ll greet Ben and Murphy, and share the troubling news from Professor McGonagall: Penny and Merula are both missing! McGonagall suspects that the Creature from the Black Lake is responsible. Together, you’ll all agree to talk things through and come up with a plan to track down the missing students.

To listen to create a plan, you need to earn five stars within one hour. The five stars are required to pass. Since this task requires a lot of energy, it is recommended to start it with a full energy bar.

Bonus progress actions are tied to Murphy and your character. Prioritize these actions to save some energy. Slide the screen left and right to check all available actions. 

You’ll agree that the best way to track down the missing students is to retrace their steps. Since Penny has only recently gone missing, it makes sense to start with her.

You’ll remember that Nymphadora Tonks and Chiara Lobosca, two Hufflepuffs who share a dorm with Penny, might have been among the last people to see her. You’ll decide to find them later and ask what they know. If you don’t already know them, you’ll receive some additional dialogue lines.

Afterwards, Ben will ask if you think Penny and Merula are all right out there, wherever they are.

There are two different options to choose from. Both of them will eventually lead to the same outcome, so feel free to take your pick.

You’ll then decide to find Chiara and Tonks to ask if they know where Penny might be.

Go to the Herbology Classroom to continue the story. If you don’t already know Chiara and Tonks, you’ll receive additional dialogue lines to introduce yourself. In any case, you’ll learn that they are also worried about Penny and will agree to tell you everything they know.

To find a lead , you need to earn five stars within three hours. The five stars are required to pass. Since this task requires a lot of energy, it is recommended to start it with a full energy bar.

The bonus progress actions are tied to Tonks. Prioritize these actions to save some energy. Slide the screen left and right to check all available actions. 

It sounds like the last time they saw Penny, she was hurrying to the Potions Classroom! They’ll mention that Penny had been in and out of there more than usual, especially after she stopped collecting the messages in bottles. 

It seems that whatever made her shift her focus from the bottles led her straight to the Potions Classroom.

You’ll then have the opportunity to ask them one more question about Penny before deciding what to do next.

There are three different options to choose from. These options will influence some dialogue that will follow, but they won’t impact the story.

Before you leave, Chiara will hand you a sprig of Dittany, explaining that it’s a powerful healing herb capable of restoring injuries to a more stable state. You’ll thank her for the thoughtful gesture, and then decide it’s time to act.

Determined and hopeful, you’ll head straight to the Potions Classroom, hoping to find Penny before it’s too late.

Proceed to the Potions Classroom when you are ready. 

When you arrive, you’ll quickly notice that Penny isn’t there — but the classroom is in complete mess. It’s clear that something happened here, and the mess is very unlike Penny, who is usually careful and organized.

Just as you start to piece things together, Professor Snape will suddenly appear at the doorway, his cloak billowing behind him. With his usual stern expression, he will demand what you are doing in his classroom.

There are three different options to choose from. All of them will eventually lead to the same outcome, so feel free to take your pick.

In any case, Professor Snape will allow you to stay and clean up the mess Penny left behind. While it might seem like punishment, it’s actually the perfect opportunity to search for clues she may have accidentally left. 

To search for clues, you need to earn five stars within three hours. The five stars are required to pass. Since this task requires a lot of energy, it is recommended to start it with a full energy bar.

Bonus progress actions are tied to Professor Snape and the books. Prioritize these actions to save some energy. 

You’ll find several of Penny’s notes scattered across the tables, and many of them say We’ll meet in the Boathouse. The Boathouse is right on the Black Lake — that could be where Penny was taken. Luckily, Professor Snape has already left and didn’t see what you found, giving you the perfect chance to act quickly. Without wasting a moment, you’ll decide to head straight to the Boathouse to see if Penny is there.

Go to the Boathouse to continue the story. When you arrive at the Boathouse, you’ll immediately hear Penny’s voice calling out from the shadows. Relieved, you’ll rush toward the sound — only to see her step out, followed by Merula. But something about Merula is deeply unsettling. 

There are three options to choose from. If you like Merula, it is recommended to pick the second option. 

In any case, Penny will quickly step between you and Merula, urging you to lower your wand. She’ll insist that everything isn’t what it seems and that she can explain everything. 

To learn the truth, you need to earn five stars within eight hours. The five stars are required to pass. Since this task requires a lot of energy, it is recommended to start it with a full energy bar.

Bonus progress actions are tied to Penny and your character. Prioritize these actions to save some energy. 

You’ll finally realize that the creature standing before you is actually Merula — though she looks pale, weakened, and deeply unsettled. Penny will turn to you, urging you to think carefully. Then she’ll say that the missing potion ingredients — Lacewing flies, Leeches, Fluxweed… — should sound familiar. What potion uses all of those ingredients in its brewing.

There are three different options to choose from. These options will influence some dialogue that will follow, but they won’t impact the story.

Penny will explain that once she put the pieces together, she wrote several copies of a message saying you’ll meet at the Boathouse and threw them into the Black Lake to try and communicate with the creature. When she came face-to-face, she was certain: Merula is under the effects of a botched Polyjuice Potion. She’ll then ask if what has happened to Merula isn’t just terrible.

There are two options to choose from. If you like Merula, it is recommended to pick the first option. 

You’ll agree that the best course of action is to take Merula to the Hospital Wing immediately.

This will mark the end of Part 3 of Creature from the Black Lake Adventure. Hit the Collect button to claim your reward. You will receive 3 Gems. As Part 3 concludes, the focus is firmly on Merula. You’ve discovered that she wasn’t the Black Lake creature after all, but a victim of a botched Polyjuice Potion.

Thanks to Penny’s quick thinking and your timely intervention, Merula is now on her way to the Hospital Wing, safe and under proper care. While she may be shaken and changed by the experience, the immediate danger has passed, giving you a moment to catch your breath before the next part of the adventure unfolds.

Thank you for reading.