Castlevania daytime cheat

In Games

Have you guys ever heard of the Castlevania daytime cheat? If yes, do you know if it is programmed into the game or made with Game Genie?

I've never heard of something like that, but in the screenshot it looks as if only the background was changed... maybe there's a gamegenie code that can do that, or maybe a patch for the NES ROM. Basically it's just changing a color, so I guess it's possible.

It's not only the color. Look: In Dracula's room there are curtains now in front of the windows. And I don't know, but if it was just a pallette swap, wouldn't the dark blue column on the left (first image) be light blue too (since it's the same color as the night sky)?

That's true with the curtains...

Where did you get the pics from?

The pics come from a person I know. But don't ask me where he got it from. When I reach him again, I can ask him.

Does anybody else here know of that cheat or what it is? I'm curious.