634. Unique Questing
Walker watched as the spirit flitted about a little here and there. "I can rest there! It's better! Faster mana! Comfortable!" The earth spirit was overjoyed to find such a comfortable place. Walker could only theorize that the runes carve on the shield were increasing the absorption of the earth elemental mana much more than it normally would with just the spirit dwelling within.
On top of this, the earth dwelling shield had been made using the skills and abilities of the earth elemental spirit. It was simple to say that this specific earth elemental spirit would have the easiest time to enter and dwell within the shield. And most likely the easiest time controlling the earth dwellings shield.