Soulstones

A Soulstone is an item that can increase your hero's stats. You can equip up to 6 soulstones. You begin the game with only one Soulstone slot, but as you increase your hero's fame you unlock more Soulstone slots.

This feature of the game is unlocked after you clear chapter 2, stage 3 [may need to be updated].

Modifying
Modifying is a way to improve Soulstones by rerolling the stats they have. Depending on your luck, modifying the Soulstone may make it better or worse.

Modifying requires Soul Dust, the cost depends on the rarity of the Soulstone and how many stats you lock while modifying. Each time you lock a stat, the cost of modifying doubles. For example, the base cost of modifying a 5 star Soulstone is 100, so locking one stat would increase this to 200, locking another would further increase the cost to 400, and so on.

Dissolving
Dissolving is one of the ways to get Soul Dusts, which is used in modifying. This essentially breaks down the Soulstones you don't want into Soul Dust. 2 Star Soulstones give 5 Dust, 3 Star Soulstones give 10 Dust, 4 Star Soulstones give 25 Dust, and 5 Star Soulstones give 50 Dust.

Soulstone Elements
Only Soulstones of 4 star rarity and above give elemental def.
 * Aero
 * Dark
 * Light
 * Fire
 * Water

4 star = 6% def

5 star = 10% def

Possible stats

 * Aero Def
 * Attack
 * Crit Def
 * Crit Dmg
 * Crit Mitg
 * Crit %
 * Dark Def
 * Defense
 * Dodge
 * Fire Def
 * Hit
 * HP
 * Light Def
 * Water Def

Legend
The color of the number indicates how good a stat is. They follow the color order for rarity.

White = Low

Green = Inferior

Blue = Medium

Pink = High

Yellow = Superb

Orange = Best