Well I had a system where you could store "relic" traits (weapons, armor, off-hand, headwear, footwear) in your reliquary if you had one. (a building that you could build in your capital holding only)
You could store relics through a diplo decision on your own character if you had a relic trait. You could use a decision in the intrigue tab to inspect your reliquary (firing a event) and take relics out of your reliquary again. If your capital got raided/sieged down there was a chance to lose stored relics to the besiegers.
The purpose of a reliquary was to store the relics that you weren't going to use since you could only wear 1 relic of the same type. Relics in the reliquary would grant you piety/prestige.
That's a nice idea. Let's hope you can reproduce that with the new feature!
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