While making their way through the later stages of The Legend of Zelda: Tears of the Kingdom' s main story, players will be introduced to a mysterious area known as the Korok Forest. This hidden area was the last known home of the 
Master Sword, and plays a key role in propelling Link into Tears of the Kingdom's endgame. When Link first arrives, it will appear to offer very little in the way of adventure. However, when the Great Deku Tree is cleansed of Gloom, the forest will once again bustle with life, offering Link several new encounters and quests.
"The Secret Room" is one such quest, now available to Link in the recently revived Korok Forest. While it is relatively small, this quest serves as a perfect introduction to the newly available content, as well as the best way to acquire the Korok Fabric for the paraglider. This guide will provide the player with everything they'll need to complete the quest with ease.
How to Begin The Secret Room in TotK
Before Link can begin "The Secret Room," it is absolutely essential that he clear the Great Deku Tree of the Gloom in its 'stomach.' Link can complete this task as part of "Trail of the Master Sword," which occurs relatively late in the main quest. If Link wishes to complete this task earlier in TotK, he can enter Korok Forest any time from a specific point in the Depths.
Once Link is prepared to begin the quest, he can fast-travel to the Musanokir Shrine. This will be available right outside the Great Deku Tree at 0410, 2133, 0144. At the base of the Deku Tree, Link should enter the same tunnel that leads to the Deku Tree Chasm.
Inside the tree, Link will find a small chamber with a cooking pot. Just before the pot, Link will want to use the Ascend ability, which will take him to the secret room where Link can initiate the mission.
Inside the secret chamber, Link will find a Korok named Oaki. He informs Link that he is trying to put together a 'secret room,' but he needs help with the decor. Complete the conversation to begin the mission.
How to Complete The Secret Room in TotK
Oaki will inform Link that he needs the following items:
-
Four
Blue Nightshades
- Two 'really vivid, bigger' Brightbloom Seeds (Giant)
Many players may already have these items by the time they reach this quest, but if they do not, see below for instructions on how to find them.
Blue Nightshade:
This material is rather uncommon in the Kingdom of Hyrule, but it is not impossible to find. There are two small ponds in the Farosh Hills that will provide Link with more than enough Blue Nightshade to complete this quest. Pond coordinates: 0599, -2470, 0080.
The Farosh Hills are found directly south of the Popla Foothills Skyview Tower (0602, -2119, 0098)
Giant Brightbloom Seed:
These larger 
Brightbloom seeds can be found in nearly every cave and well in Tears of the Kingdom. Link can find several in the Royal Hidden Passage that is revealed in the common area beneath Lookout Landing. Most stables have wells that Link can explore, most of which contain at least a few 
Giant Brightbloom seeds.
Return to Oaki:
When Link has all the required materials, return to Oaki in the secret room. The little Korok wants to see how everything looks at night, so If Link returns during the day, he'll have to wait with Oaki until nightfall.
After receiving the materials, Oaki will take a moment to set up all the decorations. He is extremely happy with the updated secret room, and will reward Link with the Korok Fabric, which he can use on the paraglider. With the mission complete, Link can now head to the Dye Shop in Hateno Village to set up his new fabric, displaying his love for Koroks for the whole Kingdom of Hyrule to see.
The Legend of Zelda: Tears of the Kingdom is available now for Nintendo Switch.