The Hogwarts Legacy Phoenix is the rarest creature that you can capture and keep in your Room of Requirement, letting you feed and groom it in order to collect the valuable Phoenix Feathers material. But here's the thing: unlike most other magical creatures, you won't be finding the Phoenix in just any old den. Instead, like the Graphorn Mount, this flame-feathered bird has some specific requirements you've got to meet before you can find it.
If you're still exploring the Highlands, you might want to know how to complete the Solved by the Bell and Cursed Tomb Treasure quests to get the special Treasure-Seeker's outfit. Otherwise, here's where to find the Hogwarts Legacy Phoenix so you can bring it back to your Room of Requirement.
Hogwarts Legacy Phoenix location
The Phoenix isn't to be found in any of the creature dens across the Highlands, but is instead linked to a specific quest. After you've unlocked the Room of Requirement, you'll receive a series of sidequests with Deek where he introduces you to the Nab-Sack and how to catch beasts so you can rescue them from Rookwood's poachers.
Once you finish the Foal of the Dead quest to breed Thestrals and care for the baby Thestral, you'll get the Phoenix Rising quest provided you are far enough in the story and have also hit level 20. Deek asks you to go and find the legendary bird in the south of the map at the Phoenix Mountain Cave Floo Flame in the Poidsear Coast region. Once inside you'll have to contend with poachers and spiders, but when you arrive at the top of the mine by the nest, you can simply take out your Nab-Sack and capture the bird.
Now all you have to do is ferry it back to the Room of Requirement, though beware of the giant spider waiting outside the mine for you.