{Author's note: Come back after reading Day 4, this won't make much sense until then}
---Adventurers, Mercenaries, and Spirit Weapons (Power)---
1st Circle: 10,000 mana - No rank
2nd Circle: 20,000 mana - Rank D
3rd Circle: 40,000 mana - Rank C
4th Circle: 80,000 mana - Rank B
5th Circle: 160,000 mana - Rank A
6th Circle: 320,000 mana - Rank S
7th Circle: 640,000 mana - Rank S
8th Circle: 1.28 million mana - Rank S
9th Circle: 2.56 million mana - Rank S
10 the Circle: 5.12 million mana - Rank S
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{Author's note: Yep, their ranking system is stupid. also don't mix up rank and grade.
Instead of the magic circle for weapons, it's how much mana was used to create it and thus its capacity.}
[Spirit Weapon Info]
•Spirit Weapon's Grade = Weapon's Ranking × Selectability Percentage
-Note: Weapon Ranking are numbered for this calculation. So Rank D is 1, Rank C is 2, etc.
•Selectability Percentage = Number of successful contracts / Total attempted contracts
---Spirit Weapon's Grade Pricing---
Grade D: 1 copper to 1 silver
Grade C: 1 silver to 1 gold
Grade B: 1 gold to 50 gold
Grade A: 50 gold to 100 gold
Grade S: 100 gold+
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For specific pricing...
Price = (higher price of the same grade - lower price) × remainder of grade calculation + lower price
Note: if the weapon has special abilities, then its price will be greatly increased depending on what ability it has
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Ex: A spirit gun shield with a power ranking of A and Selectability Percentage of 67%. It has no special abilities, it's just a gun shield with some mana.
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Gun Shield's Grade = 4 × 0.67 = 2.68
Gun Shield's Grade = 2.68, Grade C
Gun Shield's Price = 0.68 × 100 silver + 1 silver = 69 silver
Final: Gun Shield, Rank A, Grade C. Price: 69 silver
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The coins are the standard 100 copper = 1 silver. Here's a list, because lists.
---Coins---
100 copper = 1 silver
100 silver = 1 gold
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For greater increments of gold, they usually use bank notes instead of carrying it around. In other countries there are more currency types, but we have yet to get there.