Breath of the Wild’s Sunshroom Sending side quest appears after you finish the Locked Mementos quest. Before you leave the Ancient Tech Lab in Hateno Village, speak to Symin, who has a quick and useful task for you to complete and upgrade your Sheikah slate.
How to complete the Sunshroom Sending side quest
- Speak to Symin, who will tell you that you need to take a picture of a sunshroom.
- Exit the Ancient Tech Lab through the door near Symin.
- Turn right and walk to the back of the Ancient Tech Lab, where you’ll find sunshrooms. Take a picture of them.
- Return them to Symin, who will ask for more sunshroom pictures.
- Travel to Retsam Forest, which is just on the other side of the hill from the Ancient Tech Lab.
- Open your menu, navigate to the Hyrule Compendium, select the picture of the sunshroom that you took, and press A to tag it.
- Walk around Retsam Forest following the beeping beacon that’s now tuned to find sunshrooms. The stronger the signal, the closer you are to a sunshroom. It’s just like finding a shrine.
- Collect sunshrooms, and return to Symin to complete the side quest.
As a reward for completing the Sunshroom Sending side quest, you’ll receive three hearty truffles, an that item temporarily increases your maximum hearts.