Within its/her/his ancient/worn/tattered pages/leaves/vellum, secrets linger/whisper/coil. Spells/Rites/Incantations are etched/inscribed/carved in a language/tongue/cipher long forgotten/lost/obscured by time. Seekers/Adepts/Cultists of the shadowy/dark/hidden arts stumble/grapple/delve through its/her/his profound/insidious/malevolent wisdom/know