AkshatArpit
I hope Arnold says "F that" to his patron god essentially forcing him to sacrifice something in order to get stronger. Arnold needs to find his own way of doing things because obviously his god made plenty of mistakes that he seems to believe made him a more powerful person, yet he still regrets making those mistakes. Hence, its stupid to make your inheritor follow your path when you know that it was not a good one to begin with except for the power that it gave him. Let Arnold be his own person and find his own path to power.
maybe later on you may wanna do something about his unique skill as it is it'll evenually become useless once he becomes S rank on top of that while the 400% buff is good and all the skills he'll gain acess to will most likely overtake it, Maybe as a reward you can convert it to something that's A more curical in his fighting style and not an event on its own and B more usable so not lifetime usage it will most likely be a reward for reaching a certain rank or completing a trial in a different path you can also consider evolving it into something that can be used more frequently but is debuffed and has a cooldown I.E 10 minutes of 200% and 12 hour cooldown ranking him up higher with the skill may have problems though since eventually that'll become OP or useless. Maybe the evo condition can be learning a certain skill or set of skill or gaining an element like shadow(light+dark) though you can make it a more advanced element like sun(light and fire)+ corruption(special) or something with multi layers where advanced elements are combined. This is just a suggestion though this is your story and i've enjoyed reading it!(tho i'm a bit annoyed by the chapter length....) I hope you keep writing(and that i see the end of story)