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As you gain levels, you will earn various titles. Each title is earned when you reach a certain amount of HP. Each time you gain a new title you lose the previous title.

Initially (at Beginner level) you gain 1 HP every time you level up. Each higher ranking you reach increases HP growth (so you gain 2 HP per level as a Valet, 3 HP per level as a Ranger, and so forth).

Rank	HP needed
Beginner	50
Valet	55
Ranger	60
Leader	74
Battleman	90
Soldier	115
Warrior	145
Fighter	180
Swordsman	225
Trooper	280
Knight	310
Veteran	370
Master	440
Hero	510
Samurai	600
Lord	680
Lord Master	770