There is still much to do Infinity Nikki after completing chapter 8. The mission The Fifteen Years, Echoes of Wishes will unlock the new Interlude chapter for you and you will also get a nice ending by saving all the stylists.

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The quest requires you to visit Avicinda and learn more about her history, which adds much more depth to this interesting character. You will also have to find a certain key to save the stylists from their imprisoned state. By completing the mission you will finally be able to create the beautiful Silvergale costume by collecting its sketches in the new chapter.
How to Start Infinity Nikki: Fifteen Years Old, Searching for Echoes of Wishing
To start your search, you need to complete chapter 8 of the main story. Giroda is the new Master of Wishes after the events of the story, and to activate the mission, you will have to do so visit him in the Temple of Wishes using your Shrinking Outfit. Your goal is to rescue missing fashion designers locked in cages.
Fifteen Years, Echoes Of Wishes Quest Walkthrough
Your job is to get information about a key from Avicinda, who is currently facing time in prison, as he was one of Giroda's main accomplices. AS, head to Caven Prison to question him. AND located southwest of the Despair Sphere Warehouseso you can teleport to the Warp Spire to get there quickly.
The cave prison is there the same place where you saved Giroda before, when he was facing false accusations.
After talking to him, Avicinda will tell you his backstory and give you a hint on how to find the key. He will say you can you can find it near the Research Institutebut it is hidden among a pile of leaves.
How to find the key near the research institute
If you go west of the Research Instituteyou will find some piles of leaves near the rocks. You can use your purification suit to sweep away leaves. Eventually you will find the key in one of them.
If you take the wrong stack, you will be attacked with Esselings.
Now you need to give the key to the cage to the guards who are in the research institute and the stylists will be saved. You have to talk to all saved stylists to complete the search.
Fifteen years, Echoes of Wish quest rewards
After completing the mission, you can access the Interlude: Call of Beginning chapter, that you need create the Silvergale Aria dress. You can also unlock the make-up set sketch node for the Wishful Aurosa outfit in Hearts of Infinity. You will also get the following items as rewards.
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40 diamonds
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10,000 jewels
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30 strands of purity

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