I've had an idea for the grandest Castlevania game ever, since around 2005 or 2006. It has pretty much no chance of ever being made for real, but...hey, I still love this series so much I want to dream.
Features of this game:
* an immense metroidvania adventure, in 3D.
* third-person 3D. We're going to make it work this time.
* a whopping FOUR castles, each with a different set of about ten to thirteen areas, with the areas roughly corresponding to each other thematically.
* a soundtrack heavily drawn from the rest of the Castlevania series -- so far I've planned to include music from all seven "castletroids", as well as Super IV, Bloodlines, Haunted Castle, Dracula's Curse, and others. (Yes, this means finally giving Harmony of Dissonance's soundtrack the glory it deserves.)
* areas and bosses inspired by areas, bosses, and music tracks of other Castlevania games.
* gated progression through the game -- explore most of each castle to get to subsequent ones, and defeat select bosses in order to reach further bosses. Sequence breaking may be possible.
* subweapons to be collected as metroidvania-style powerups, in addition to some powerups that have appeared as other castletroids.