Nerida Robert's mermaid necklace may be kept or returned in Hogwarts Legacy. Here's what happens in both choices, as well as how to complete the Mer-Ky Depths quest given to you by the Slytherin student.
Nerida's mermaid necklace should you keep or return it in Hogwarts Legacy?
Nerida Roberts will be seen for the first time in the Hogwarts Boathouse, where she offers you the Mer-Ky Depths quest. In the mission, the Slytherin student asks you to retrieve a mermaid gift that the merpeople have given to her as a peace offering. You will then be given the choice of returning the necklace to Nerida or keeping it for yourself.
Both choices earn 180 experience points and a Mermish Liason Uniform. The outcome will be the same, although Nerida Roberts may be irritated if you keep the mermaid necklace, as Hogwarts Legacy doesn't have a relationship system, so there will be no further missions with Nerida.
How to Finish the Mer-Ky Depths quest
After talking with Nerida, swim up to the marked waypoint to get under the lake. Once you've reached the cavern, release the two trapped insects by casting the Incendio spell on the cobwebs. Next, use Lumos to carry each insect to the door to lock them in place.
The last moth will be hidden under a pillar at the back of the room, so return to the entrance to grab it. The door will automatically unlock to reveal a chest, so remove the treasure and give it to Nerida. You may now choose to keep or give the gift to Roberts.
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