Vivatus Fides Ballista [2]

Can't be destroyed.
Increases Arrow Storm damage by 10%.
Atk + 18 per 3 refine rate.
If refine rate is 7 or higher, increases Arrow Storm damage by additional 20%.
If refine rate is 9 or higher, reduces cooldown of Arrow Storm by 1.2 seconds.
If refine rate is 11 or higher, increases Arrow Storm damage by additional 25%.
If refine rate is 12 or higher, increases long ranged physical damage by 15%.
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[Bonus by grade]
[Grade D] If refine rate is 11 or higher, increases physical damage againt all property enemies by 15%.
[Grade C] Increases Arrow Storm damage by additional 15%.
[Grade B] Atk + 7%.
[Grade A] POW + 1 and P.Atk + 1 per 3 refine rate.