The titular system is brought in about 70 chapters in- dream master. Which allows you to go into dream worlds... which can have their own cultivation systems (the one in the first world it is pretty silly, with like....20 distinct level names and things like 99 tribulations in a 'we have cool magic items' setting; very dream logic based, so that is easy to write off). At first, this seemed like it was just a "lol, do whatever" method of training your mind/soul/magic- you can do whatever in the dream world without worrying about dying or hostages. There is also an hint that he can set the setting, so he can make his own scenarios to live through.
But then, the character brings up how dream masters can bring certain things into the real world if they 'follow natural laws of the real world'. Which seems more like he is modding skyrim and he can only insert certain files of the right type. This makes me realize that the other systems in the 'real world' are probably just things that dream masters imported in.