Yeah that was one of the darker chapters so far but Casey wasn't going to sugar coat it. And trust me, we've only scratched the surface. That was only the Gamma level, which is one of the bottom levels. As the story progresses youll get to see more of what goes on.

As for what happened during the fours years of his life that he lost, well it was mainly his transformation into a Gijinka but that will be developed later on when you meet the main antagonists for the story.