Do you mean you want examples of Castlevania music that is inspired from progressive rock? That's pretty easy. Huge portions of the first four games in the series is full of it. Just listen through those soundtracks. Or do you mean you want examples of bands who have delved into similar progressive rock/jazz sounds? Jeez, I mean, there are hundreds. But I supposed examples where you can easily find similar music would be found in the discographies of King Crimson, Yes, Iron Maiden, Tool, Porcupine Tree, Opeth, and really, I could go on and on...There's just a lot to be found in the programmed bass lines, keys, organs, drums, beats, harmonies, etc.; a very prevalent progressive sound overall.