According to chapter-1 of this novel, here's a breakdown of Zanthrix's 'Rank Up System' that differs him from all the other players and their 'Level Up System'
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[CHARACTER PROFILE]
[Name: Zanthrix]
[Rank: D]
[Job: None]
[Title: The Fallen Heir]*
[Blessings: None]
[PLAYER STATUS]
[Health: 1860/1860]
[Stamina:0/410]
[Fatigue: 0%]
[Skill Gauge: 0%]
[CORE ATTRIBUTES]
[STR: 39]
[AGI: 41]
[DEF: 35]
[ACC: 38]
[PEN: 36]
[INT: 40]
[VIT: 42]
[ADDITIONAL ATTRIBUTES]
[AOE (Area of Effect): Lv-2]
Increases the area of effectiveness while using a area based attack. Current area: 5 meter (in Lv-2)
[HBR (Health Buffer Rate): Lv-1]
Recovers Health. Ten HP per second for five second (in Lv-1). Cooldown: 1 Hour
[SRR (Skill Recast Reducer): Lv-2]
Reduces recast time by 10% (in Lv-2) when using Class Exclusive skills.
[SEA (Skill Effect Amplifier):Lv-2]
Enhances efficiency of an skill based attack by 10% (in Lv-2)
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[Avatar Exclusive Skill: Class Shifter (Stage-2)
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[PRIMARY CLASSES]
[Swordsman (Tier-6) (+20 STR)]
[Assassin (Tier-6) (+20 AGI)]
[Defender (Tier-7) (+15 DEF)]
[Archer (Tier-7) (+15 ACC)]
[Lancer (Tier-7) (+15 PEN)]
[Mage (Tier-6) (+20 INT)]
[Supporter (Tier-7) (+15 VIT)]
[Rampager (LOCKED)]
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[SECONDARY CLASSES]
[Summoner]
(Contracted Summoning Seraphyll)
[Zariel (Type: Inferior); The Ruler of Thunder]
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[Note: Title 'The Fallen Heir' has a significant role in Zanthrix's adventure. However it's still not active yet]