Castlevania: Legacy of Darkness
Often during the development of a video game demo versions of the game will be shown and released that end up looking quite different from the final product. This can happen for a number of reasons, from changes to the engine to new ideas being added in during the development process. Other times, though, a game has to be released by a certain deadline (a common occurence in an industry where annual earnings are dependent on the release of select AAA titles) and promised features have to be removed from a game to get it to completion on time.
Such was the case with Castlevania for the Nintendo 64. The game, as demoed featured two characters that weren't available in the final game. Most likely cut due to time constraints, the characters were removed as were their relevant boss fights and plotlines. Since this was before the age of every console having an internet connection, the only way to have any of the features added back in was to release a new edition of the game, which Konami did as Legacy of Darkness.
Ostensibly called a "prequel" to Castlevania 64, the first portion of the game follows the story of Cornell, a werewolf drawn into Dracula's web when the follower's of the Dark Prince kidnap the werewolf's adopted sister. Cornell has to venture through a castle that's very similar to the one in Castlevania 64 and save his sister, along the way fghting some new bosses and meeting a few new faces along the way. And then, after playing through as Cornell, players can take on Henry Oldrey, a child Cornell saved who returns to the castle years later on a quest to save more children from Dracula's clutches. From there, the players can then replay (lightly remixed versions of) Reinhardt and Carrie's quests if they so desire.
And that, right there, is the biggest issue between the two games. Because they're both so similar, featuring largely the same areas to explore, enemies to fight, and quests to run through, Legacy comes across as little more than an expansion pack for it's predecessor -- a "director's cut" put out at full price when it was first released. It has a bad reputation not just because the original Castlevania 64 was a bit of a mess but because it doesn't add that much new to the package and then charged full price for it.
The game was largely ignored by all but the most hardcore of fans, and the saga of Castlevania 64 came to a sad, quiet end. The next time Konami would try to make a 3D Castlevania they would go in a completely different direction, as if trying to ignore that these games even existed -- which, according to the chronology of the series by Konami, they don't.