The reason he thought the demonking was weak, was because he was too pre-occupied with the fight that he did not notice the Negative job effect of the demon king.
He only took the long route is because his "allies" dragged him all over the world, for meaningless jobs.
in the 2nd route he took the easy way. demanding money, beating the dragon, and the demon-king.
Noticing the Negative skill effect, due the Demonking being occupied by the elven queen.
he could analyze the skills of the demon king.
he also abused all knowledge he had from the 1st route to avoid everything that could make his journey last longer.
In the 3rd route it somewhat went like the 2nd one, only then he had the blackbox skill,
he did have 1 "ally/burden" that dragged him down, as he wanted to do good by using the blackbox skill. and some info he had from his last life.
the 4th round, he Killed the demonking right away, because he kept the Holy sword 2. and all his skills
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Hero festival arc. {up till this point that is how it went, havent read the novel, so cant say much more}
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