The following schema sets out the difficulty ranking schema used by UBerserker in his custom map walkthroughs.
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One Star: the maps can be completed just with Dispersion Pistol (DP) and with other weapons in certain situations if you want. This is also valid for maps that don't have fights and are just for a walk. |
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Two Stars: the maps can be completed with DP, but there are some battles forcing you using other weapons. The fights are nothing hard anyway. |
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Three Stars: the maps are starting to get tough. Many battles are serious in this case, forcing you to do strategies. A step up from two stars anyway, less DP, more other weapons. |
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Four Stars: the maps are just hard. Every battles are hard and require real strategies, otherwise you'll never get through. Luck starts also to be useful. |
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Five Stars: a step up from "four stars maps". Battles are even more harder, strategies must be deeper and luck is unfortunately a factor you sometime need. You'll probably die a lot here. |
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Six Stars: a special rank. It can be two things: the first is just any of the situation above, but in the map there will be an unfair battle which just require luck or cheating. The second thing is that the map will be like a "five stars" one, and the battle are or quite unfair. |
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Seven Stars: the last special rank. This is for impossible maps with unfair challenges. These force you to cheat. |