Defines which of six categories this AI’s vision falls into. Objects can be made more or less visible to AIs in each category by applying AI Core→Visibility Modifier to them. An AI without this property will not use the Visibility Modifier at all.
The value of this property is an integer from 0 to 5. in System Shock 2 the categories are named:
In Thief 2, the property is present but unused by the stock missions.