Soul Prison
From The Heroes of Might and Magic III wiki
Grail building for the Necropolis.
To build this structure, find and bring the Grail artifact to a Necropolis town, and click on the Village/Town/City Hall or Capitol, and you will be asked if this is where you want the permanent home of the Grail to be.
The Grail grants the following to all town types:
- 5000 extra gold per day
- 50% additional creature growth
The Soul Prison in particular also:
- Increases the Necromancy skill of all allied heroes by 20%.
