You get a free skill every 5 Levels
Level 1: First-Stage Skill
Level 5: Second-Stage Skill
Level 10: Third-Stage Skill
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A first-stage skill scroll is a skill you can learn even if you are Level one, to learn a skill from a second-stage skill scroll, you have to be Level 5, to learn a skill from a third-stage skill scroll you hava to be Level 10 etc.