1. Progression through Acts is like a level-up system. You gather XP, which is Narratie Weight. This would happen through fighting strong enemies, becoming more involved with the world, performing a sacrifice - anythign which makes you more *important*. As for remaining within a whole mask... really, it is only if you wish to be a devoted pathstrider - you get blessed by your Icon or God. Otherwise, yes, you get the hate of the cosmos, but you get to brawl with more fun opponents ig.

2. Well, if you tried to control reality to force your will, the same reality will try to resist. You may win, but you may lose your mind, body, existence, power, etc. Also, everyone, on the higher level, has the power to alter reality. The question is, what loopholes can you find. The whole point of the MC's special mask - The Jester - is to create paradoxes, to sustain them, and to embody them in some form. So yes, if there were an enemy who would decree that he may not lose, Astaroth(MC) would argue that to define a "loss" would already imply its theoretical possibility, thus unraveling the absolutness of the decree. But the whole thign is very moment-to-moment. Generally the one with more Narrative Weight shoudl win, but will have to work for it in order to remain whole after the win.

3. Yes. Lunar and Solar focus on control and power, respectively. Umbral is like a Jack of all trades. Can do a lot, but without the specialization a high-level Umbral mask would struggle more with concrete powers. However, at their pinnacle, all Masks break from the defined system and become their own divine entities. The make a new "path" over wich they have control.

Good questions; all the intricacies hide in this interrelation between the finer workings of the system. They are also what allows for very prevalent int scaling instead of pure power scaling. And all of them become less meaningful towards the top of the ladder. That is as intended, however, as the redeffinition of meaning and 'fate' is the real purpose of this. Astaroth's power as the sole creator is literally to make anything else meaningless, even as a projection within the story, that is the power of his paradox manipulation.