'My upgrader skill is acting up which means I can combine this skill with others. But this time it's an S rank skill so the result should be better.'
'Huu. Before I combine my skills. I should collect the new one too.'
For clearing the Labyrinth Shin also got a Purple Skill Book. With a skill book, a person can learn a random skill without any penalties. Finding a skill book is also not common.
Skill books are graded with color and depending on the color the skill of that rank can come out.
White --> H - F rank skill.
Yellow --> F - D rank skill.
Green --> D - C rank skill.
Orange --> C - B rank skill
Red --> B - A rank skill.
Purple --> A - S rank skill.
Golden --> S rank and above.
Further details unknown.
A skill book can only be used once and by one person. So they are rare and the purple skill book was one of the rarest ones.
