The Golden Order Principia is one of the prayerbooks you can find throughout the Lands Between. This prayerbook allows you to learn two additional incantations; Radagon’s Rings of Light and Law of Regression. Radagon’s Rings of Light creates large rings of light that can deal a lot of damage while the Law of Regression allows you to heal all ailments affecting you. Here is where you can find the Golden Order Principia in Elden Ring.
To obtain this prayerbook, you will first need to get into the capital city in Altus Plateau. This is done by obtaining at least two Great Runes and defeating the Draconic Tree Sentinel boss. You can obtain Great Runes from Rykard, Godrick, and Radahn to allow you to access the capital city. Once you get into the city, you will need to make your way down to the main road and over to the dragon’s wing. Climb the dragon’s wing and then the tree roots to gain access to Godfrey’s boss room.
Defeat Godfrey and you will be able to search the boss room. Go outside to the balcony and climb on the tree roots to gain access to the upper level of the boss arena. Go out the door, hang a left, and jump on the roof. Go through the broken window to gain access to the other part of the upper level. Follow the balcony around to the tree root on the other side. Hop on the tree root and grab the prayerbook from the chair hanging from the ceiling. You do not need to jump on the chair to get the prayerbook, standing on the tree roots will work.
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