Touch Of The Heavenly Host Insignia
When visiting an eligible room and wielding the quest weapon, you may be shown a special message indicating that it's an activation room. IIRC this message mentions something about a glimmering in the air -- and it reportedly may not be shown during the night time??
Depending on the place of activation and depending on the time of day, bonuses can vary. Remember not to lose the weapon from Restoring Mark V (Part 1) Quest as wielding it is required when performing the activation.
- Modifies spell power by + 5% continuous - Zodiac, in Dusk's room (Autumn Descending)
- Modifies hit roll by 4 continuous - Deepways
- Modifies hp regeneration by + 50% continuous - Graw Akkuurattaan, in Jaur's room (The Fallen Angel)
- Modifies mana regeneration by + 50% continuous - Tiureess
- Modifies hp by 125 continuous - Sphynx Gate
- Modifies mana by 300 continuous, Modifies hp by 300 continuous - Airways
- Modifies armor class by -10 continuous - Fungal Forest
- Modifies mana by 500 continuous - Defender's Graveyard
(More exist undiscovered)