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An old amethyst text titled the Cataracta Abscondita hides perfectly among the other ancient texts in the Horned Serpent library. If a Serpent removes it from the shelf it resides on, the shelf will swing open to reveal a rock formation surrounded by lush greenery. It is a peaceful and silent area, but no Serpent leaves it how it is.

On page 1603 of the Cataracta Abscondita (placed there because of Isolt Sayre’s year of birth) is a Latin incantation - A animi ut clarum est, sicut aqua multo pretiosior auro (translation: A mind as clear as water is more valuable than gold). By reciting this incantation, water will spring forth from the top of the rocks and glide gracefully into the pool below it.

The waters of the hidden pool are enchanted to aid in clearing the mind of those who let the clear waterfall rush over them. By sitting under the falls and listening to the rushing, rain-like sounds, Serpents’ brains are slowly uncluttered and calmed, which is a much-needed helpmate in the House of those with active, brilliant minds.

The bookshelf, which swings shut behind the Serpent, can be opened again by touching the Cataracta Abscondita to the wooden back of the shelf. The Serpent returns the book to its place and goes their way, leaving the pool and waterfall for another to use.