Seems like shift level up chance for no star vanilla creatures might affect some creatures which have stars in vanilla.
Limited testing, but noticed with fluid second factor on medium difficulty, no wolves or drakes appeared with stars in mountains over several irl days. Killed bonemass, so expected world level would be 1 in mountains AFAIK, tested changing to custom difficulty and setting chance to 94,5,1,0,0 for world level 1, ie zero chance for no star. Enabled devcommands and fly to fly around in unexplored areas of mountains, still only zero star spawns. Tried changing shift level up chance for no star vanilla creatures to 0, after which all new spawns appears to be 1+ star in mountains
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