Oman Au Shrine
Northeastern Great Plateau
Oman Au Shrine, also known as the Magnesis Trial, is one of the many Shrine of Trials from Breath of the Wild.
Breath of the Wild
Early on in Link's quest, he will raise the Great Plateau Tower and shortly after that, the Old Man will seek Link out. The Old Man tells Link that in order to leave the Great Plateau, Link must first acquire the Paraglider. The Old Man points Link in the direction of the Oman Au Shrine, stating that there most likely is some nice treasure deep inside and that he will trade the Paraglider for that treasure. Oman Au Shrine is one of the required Shrines that Link must complete in order to progress in the game. While the Old Man points Link in the direction of Oman Au Shrine, Link can complete the first four Shrines in any desired order.
The Old Man will point Link towards the Oman Au Shrine. It is located just northwest of the Great Plateau Tower and it is the closest shrine to the tower.
At the nearby pedestal, Link will acquire the Magnesis Rune for his Sheikah Slate. This Rune will give Link the Magnesis ability, which allows Link to move metallic objects within a certain range. The Shrine acts as a tutorial for this ability.
Use the Magnesis Rune to lift up one or both of the plates in the first room, and continue through the passage underneath.
You'll come to a wall of stone blocks, with one metal block right in middle. Use the Magnesis rune on the metal block to knock down the other blocks, or create a staircase so that Link can pass. On the other side is a simple Guardian Scout I, or a Guardian Scout II if playing Master Mode.
Cross the metal plate that acts as a bridge, and then turn around and use Magnesis on the metal plate to grab it. Carry it to the other side and use it to cross the next gap.
At this point, up on the ledge to the left is a treasure chest that contains a Traveler's Bow. Use the Magnesis rune to pull it to within your reach and open it.
Use the Magnesis rune to pull open the metal doors ahead, and continue to the altar. Examine the altar to complete the trial and receive a Spirit Orb.