Magic spells increases in level with use. Also, there are numbers
next to a magic spell. For example : [ Esuna 1 - 0 ]
The number on the left is the magic's level, and the one to the right is
the spell's "experience meter". This number goes every time you use a
spell. And once it reaches 100, that spell gains a level. Which in turn
makes it stronger and more effective.
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