The Proving Ground shrines task Link with fighting Constructs using nothing but what is supplied. In the Simosiwak Shrine, all the lights are out and Link receives only a stick and a shield with a flashlight. The good news is that there are only three Constructs to defeat. The bad news is that they hit hard!
Simosiwak Shrine (Proving Grounds: Lights Out)
The Simosiwak Shrine (Proving Grounds: Lights Out) is located on Bravery Island, a floating island near the North Hyrule Sky Archipelago directly above the Great Hyrule Forest. This shrine is located at coordinates: 0163, 1972, 0759. To unlock this shrine, speak with the nearby Construct and complete the ring diving tutorial. This will cause the shrine to appear. You can return to the Construct again and complete its challenge to earn the gliding pants.
As for the shrine, it is pitch black and Link is stripped of all his resources. This means you will need to rely on whatever you can scrounge from the shrine itself. To start with, grab the light shields and stick from beside the steps. The shield will be a valuable source of light.
To complete the shrine, defeat all of the Constructs you can find. Enter the dark room and immediately go to the right. Head up the stairs and defeat the Construct at the top. If you’re quick, you can use Fuse to attach any rubies on the ground to your stick, vastly improving its damage output.
The next Construct can be seen patrolling along the left side of the arena. It has a light shield which you can use if yours runs out of juice. With the second Construct done, the last Construct is in the far left corner and it uses a Zonai flame device and a light shield. Try to smack it down quickly and avoid getting burned.
Once all three Constructs are defeated, Link will get his gear back and the door will open. Go through, open the chest to receive a Bright Elixir and then get your Light of Blessing. We’ve got heaps more shrine walkthroughs on our Zelda: Tears of the Kingdom Strategy Guide.