The main reason Hero seems so imbalanced is because the requirements for unlocking it were released so far ahead that it allowed a lot of people to unlock it immediately; the reason why SEGA says it is working as intended is because in their eyes it is a class that you can only use after you have worked for it, thus the large power boost is a reward for having leveled up multiple classes to lv75. Obviously, this isn't the case thanks to the current slew of boosts we've had thanks to the WEB Panel event, but in theory, it should hold true for players who start after this point.
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