Aldûr: The First Age
Præphora bells, named after the third daughter of Lord Thuul of Gilden’s House Zhenir, who derived the alchemy to reduce the Bell of Xakirn, are created from silver smelted from the original bell and mixed with some essence of the entity it is sought to effect.
When struck, a Præphora bell does one of two things; the attuned entity is stunned for 2d4 rounds or the essence of the entity is trapped and retained within the flute of the bell. The essence returns to the body within 2d4 rounds unless the bell is mounted within a copper cage which has likewise been arcanely attuned to the same essence.
Approximately twenty six bells were created from the original Bell of Xakirn. Thirteen were said to be mounted within gilded cages.