The thirty-fifth main quest in Hogwarts Legacy is Niamh Fitzgerald’s Trial where you need to head to the Headmaster’s office to experience a unique trial.
You can obtain this quest after you get the password from The Polyjuice Plot quest.
In order to complete the quest, simply follow this guide.
How to Complete the Niamh Fitzgerald’s Trial Quest
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Start the quest by heading to the Headmaster’s Office.
You can quickly get to it by fast-traveling to the Trophy Room Floo Flame, unlocking the double gates, and ascending the stairwell until you reach the top and find a Griffin statue.
Whisper the password you’ve received while doing the quest, The Polyjuice Plot, onto the Griffin statue to open it.
After whispering the password, a spiral staircase will appear; ascending the stairs will let you reach the Headmaster’s office.
Source: ZaFrostPet
Once you step inside the Headmaster’s office, the painting of Niamh will tell you to read a book at the back of the room up a small staircase.
Go to the location mentioned by Niamh and read the book on top of the pedestal. This will then transport your character into a black-and-white world, allowing you to interact with the three Deathly Hallows.
Remain Undetected
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In the black-and-white world, cross the bridge to trigger a cutscene where a large embodiment of Death slams its hand onto the ground and hits villagers, turning them into Death’s Shadow.
Avoid them at all costs; if even one of them notices you, it will result in instant death and failing the mission.
Source: ZaFrostPet
This will be a long stealth section where you must reach a mysterious cloak while avoiding getting seen by Death’s Shadow.
Use the Invisibility Cloak
With the Invisibility cloak you’re wearing, you can get near Death’s Shadow and waltz through them to reach the next destination.
After the Invisibility Cloak, you will enter the white space again and encounter a Mysterious Wand which is actually the Elder Wand.
Grab the wand to access your spells while having a temporary spell cooldown reduction.
Destroy the rubble blocking your path with Bombarda, then defeat all of Death’s Shadow in your way while using the most powerful wand in the Wizarding World.
Once you reach the castle, you will fight two waves of enemies.
The first wave has Death’s Shadows and two Death’s Trolls while the second wave consists of Death’s Shadows, Death’s Dark Mongrel, and two Death’s Trolls simultaneously.
After clearing the enemies, go to the left of the arena, descend the steps, and step onto the podium to enter the white space again.
Complete the Trial of the Stone
In the white space, you will encounter the last piece of the Deathly Hallows, the Resurrection Stone.
Grab the stone, then follow the path to reach the body of Niamh. Use the stone to revive her.
Once Niamh wakes up, follow her towards the giant statue to find a Pensieve that will allow you to experience a part of Niamh’s memories.
The memory will be about Niamh confronting Isidora about her experimentation with magic surrounding emotions and removing one’s pain.
After the cutscene, walk towards the enchanted archway to enter the Map Chamber.
Once inside the Map Chamber, head to the Keepers to be introduced to the fourth and last Keeper, San Bakar. The mission will be completed after talking to him.
