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"The hungry trees will show you the way. Spy their iron to win the day."

Trial of Second Sight is a Shrine quest in The Legend of Zelda: Breath of the Wild. The quest is obtained from Zooki along the southwest path out of Korok Forest. The quest simply calls for Link to travel through the forest without getting lost, though the trail is laced with "hungry trees" holding metal boulders in their mouths which can easily be seen through the mist using the Sheikah Slate's Magnesis Rune. About halfway through, the trail of metal boulders ends with a Rusty Shield lodged into a tree trunk in the middle of a clearing guarded by three Stalkoblins. A plaque before another hungry tree instructs Link to feed it the shield, which can be done using the Magnesis Rune. Once this is done, a Chest containing an Amber will appear in the mouth of a nearby tree and a path is revealed to a small island in the middle of a lake with a second plaque placed in front of another hungry tree. This plaque instructs Link to place the chest which appeared earlier into the island tree's mouth. Once this is done, a shrine will emerge from the ground nearby and the quest is completed.

Spoiler warning: Spoilers end here.