Absolutely love this game, but am really curious currently unable to be bought what is the utility of the half face stone sculpture? Will it make us stronger, is it something like the stone mask from Jojo?

Firstly, I am having a blast with this game, it's my favorite game in this genre. But I was wondering when or if the walkthrough will be updated? Either I'm miscounting or the walkthrough doesn't have information for the prison arc.