LOL, the shit starts as the usual fantasy tale then takes a nose dive into WTFville with a gasoline jacket to hell.
I can't stress enough that if you enjoyed the anime you NEED to read the manga. Even if you don't do the comic/manga thing, this is a case where you should make an exception. Kenturo Muira is one of the greatest mangaka you will ever see draw a page and the story he's written so far is more fucked up, yet more complex, than what the anime is probably allowed to show. It's also just great story telling and Guts is one the best protagonist I've ever read. You could almost say he's similar to Jamie from GOT with how he develops over time. The sad part is that Kenturo is on that GRRM shit. Berserk is over 20 years old and we still we may never get a conclusion to this shit.