This guide shows how to complete the objective ‘Search for the key near the Weeping Willow‘ for the Witling Weeping Willow quest in Genshin Impact 4.2.
To complete the objective, teleport to the location marked on the map below. Enter the cave and dive into the water. Follow the cave path until you find an altar at the bottom
In order for a drop-key to appear on the altar. First of all, you need to free the xenochrome globular octopus in order to use its ability. Swim up to the Xenocromatic Creatures on the right side and borrow the skill by pressing the left mouse button.
Use Xenocromatic Creatures’ ability to cut the seaweed above the altar where an octopus is caged.
Then, acquire the skill from the xenochrome globular octopus and clean the contaminated mucus near the altar.
This will release a Dew Bubble in the area. Now you must move this Dew bubble to the altar using the octopus ability. Place the Dew bubble in the middle of the altar, so that the bursting Dew bubble will activate the Reed Pipe. The Harmonious Reed Pipe requires the ripples released by bursting Dew Bubbles to be activated.