The Secret Door (Level 10) 

The Secret Door
Mickey needs your help with something he found.
Minnie returned to the Village, bringing with her the memory of a magical chest Mickey hid. He has found it again but is unable to open it, and thinks you’re the perfect candidate to try.
The chest turns into a Memory, and a discussion with Mickey puts you on the path toward a secret door — hidden somewhere in Dreamlight Valley.
You find the secret door inside the Castle. Mickey remembers the second part of the riddle. Maybe it’ll help you open it.
You can get this quest after getting Mickey to Friendship level 10. After completing this quest, Mickey will give you an Enchanting Fountain. Here you can find all your subjects for the quest and explanations behind it.

• Try opening Mickey’s chest in your inventory: go to your backpack and open the chest.
• Talk to Mickey: you can see on the map where he is.
• Refer to Mickey’s Memory to find the secret door: Go inside the dream castle. Go right behind some trees, there you will find the door.
• You found the door! Use your magic on the curtain: interact with the curtain.
• Talk to Mickey: Mickey followed you inside the castle.
• Use the riddle to unlock the Secret Door: find 4 gemstones with mining in your village. A Garnet (Plaza and Peaceful Meadow), A Citrine (The Glade Of Trust and Sunlit Plateau), an Aquamarine (Dazzle Beach and The Forest of Valor) and a Tourmaline (The Frosted Heights and Sunlit Plateau). After finding the 4 gemstones, place them in the door. 
• You did it! Go inside and see what’s there: go behind the door.
• What’s in this secret room? Talk to Mickey to see what he remembers: he follows you inside the room. With talking to him, you complete this quest.