This book whispers arcane knowledge into its reader's brain. By using this book, you obtain the ability to cast some spells as rituals. You are considered a primary spellcaster for this purpose, intelligence is your spellcasting ability, and you must meet the required level to cast the spells.
While casting a ritual through this book, you must succeed on an intelligence saving throw DC 10 + the level of the spell. If you fail, you receive 1d4 psychic damage per spell level, and your maximum hit points are reduced by the same amount until the end of your next long rest, unless you benefit from a Greater Restauration spell.
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