This is a hack I found on a castlevania forum. I was gonna submit it to the site but haven't gotten around to making a patch. Here is a link to the forum.

http://castlevania.classicgaming.gamespy.com/forums/index.php?topic=70&start=0

Here's some pictures.


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This is based on the japanese version of HOD so Belmont becomes Belmondo, and most of the text is in japanese but it's still good fun. Whats been done is impressive. Several characters have been added. Music has been added. Graphics changed. If anyone wants to go ahead and make a patch and submit it to the site go for it. I will if noone else does, but it might take time since I don't have regular access to the internet. Revenge on the Findesiecle seems to be the name of the hack, I have no idea what that means.

"Revenge on the Fin de Siecle"...that makes about as much sense as the lyrics "You will submit to the decoupage!" in the Strong Bad Email death metal.

Graphics changes? Easy, because the sprites aren't compressed so far as I can tell in the game. The music was almost certainly done with the utility Sappy. The palettes and such would be easily found (If you know how to debug with even basic ability) with something like VBA's debugger.

So far as learning, there's a virtual Library of Alexandria on ROM hacking on this site. However, a lot of what it takes to be a good hacker just comes from experience: Many, many things that are done are based on semi-educated guessing and the strange, hard to quantify abilities that come when delving into something deeply. I've been involved with some of the most extensive NES hacks to ever be created, but I'm maybe an average hacker at best (Most people here slay me so far as technical prowess).