Date's Challenge is a World Quest that unlocks after you solve the Labyrinth puzzle in the Evernight Temple. After completing the prerequisite, enter the gate on the floor and meet the afterimage of Date (your daylight setting must be set to Evernight).
Speak with him, and he'll tell you that he was the second-best architect in the entirety of Byakuyakoku. He once created an intricate Labyrinth that he wants you to solve. He'll give you Date's Key to access it.
Follow the quest marker to the Serpent's Heart, where you'll find a mechanism and a locked gate—also on the floor. Interact with the mechanism using Date's Key and jump down to reach the puzzle room.
Assuming that the locked chest is behind you, reference the image above to help you solve the puzzle. There are two levers—one on the frontmost pillar and another on the pillar at the very back. There's a triangle mechanism on the left and right side of the room, and at the very front is a day-night switch mechanism.
Follow these exact steps to solve the puzzle.
- Switch the daylight setting to Whitenight.
- Interact with lever A.
- Attack triangular mechanism C twice. This should make the stone wall move twice as well. If the stone wall only moves once, try again.
- Interact with lever A.
- Attack triangular mechanism D once, which should prompt the stone wall to move once as well.
- Interact with lever A.
- Inreract with lever B.
- Interact with lever A.
- Attack triangular mechanism D twice. This should force two different stone walls to move. If only one moves, try again.
- Interact with lever B.
- Attack triangular mechanism C.
- Switch the daylight setting to Evernight.
The Luxurious Chest behind you should unlock, granting you Date's Medal of Recognition and the Wonders of the World Achievement called "Maybe Get Yourself a More Social Hobby..."
Follow the quest marker back to Date in the Evernight Temple. Speak with him, then turn left and unlock the gate using the two Date's Medal of Recognition. Inside, you'll find an Exquisite Chest that contains the Hydrological Studies in Byakuyakoku, a book required for the Collection of Dragons and Snakes World Quest.
Check out our guide on How to complete the Tricolor File World Quest in Enkanomiya Genshin Impact to obtain another book for the Collection of Dragons and Snakes.