In the vein of a world filled with spirits there are rare items to be discovered that contain spirits within.

An item of such a nature will not fully be realized until the spirit is called forth out of the item.

Items carrying such require you to explore through each of the 12 guardian shrines to see if they glow to attunement of any particular deity. Once attuned you can open forth a rift and try to unleash the full power of the item. Whether it be fighting a boss of some sort or exploring through a tail weaved by the power of previous wielders of the item.

This falls inline with the power of echo and utilizing it to see within things or events of the past.