quest difficulty:
1-Star (1*): the quest target at least has a peak normal human power or the target is protected by something or someone in a peak normal human strength
2-Star (2*): the quest target at least is a city-level powerhouse or protected by something or someone on the same level
3-Star (3*): the target is at least a country-level powerhouse or protected by something or someone on the same level
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4 and 5 Star (4*/5*): the target is a continental-level powerhouse
6 and 7 Star (6*/7*): the target is a planetary-level powerhouse
8 and 9 Star (8*/9*): the target is a world/ universe-level powerhouse
10-Star (10*): the target is a multiversal-level powerhouse
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the world rating is based on how many peak-level powerhouses are and how aggressive their action toward Kaoru and other members
1-Star (1*) world: a relatively safe world where as long as Kaoru and the others didn't actively provoke the strongest being in that world the chance they could survive is almost 100%.
2-Star (2*) world: a world where as long as they are careful they will probably be safe.
3-Star (3*) world: the problem will come MC's way even if they didn't try to trigger it.
4-Star (4*) world: absolutely dangerous world because with just one wrong move it will be game over.
5-Star (5*) world (chaotic): an impossible world where just by appearing in that world all the peak powerhouse will know about them and maybe or maybe not will try to erase them.