void main()
{

   object oCreature = GetEnteringObject();
   object oDark = GetObjectByTag("darkness");
   location oLoc = GetLocation(oDark);
   effect eDarkness = EffectVisualEffect(VFX_DUR_DARKNESS);
   ApplyEffectToObject(DURATION_TYPE_PERMANENT, eDarkness, oDark);

}