When the Castlevania series made the jump to 3D, it's not hard to to assume that Konami wanted to try and carry over as many elements of the past series as they could to the new platform. To that end they gave the game not only a Belmont analogue (Reinhardt Schneider) but also a Belnades decendent, too: Carrie Fernandez. THis allowed the game to make certain connections with past entries in the series -- namely Castlevania III: Dracula's Curse and it's Belmont and Belnades characters.
The first Castlevania game for the Nintendo 64 actually had a few character initially planned for it (two of which had to be cut for time but were restored in the director's cut, Castlevania: Legacy of Darkness), showing that the developers really were passionate about what they were making. However, despite their intentions, the game that was released wasn't as good as fans would have liked. Although we at the Inverted Dungeon have a soft place in our hearts for the games, we will admit they aren't that great. Still, it's not for a lack of ideas and heart that the games suffered -- they certainly tried to put as much into the games as they could. Maybe to a fault, considering how much was cut down.
Carrie suffered some during development. Although she's a Belnades by blood, she really doesn't play like one. She has magic orbs she can cast as her primary attack but none of the traditional Belnades spells. If not for the fact that the game makes it clear Carrie is a Belnades decendent you'd be hard pressed to know it otherwise. Any features that might have been planned to make her more unique were never put into either game (probably due to space issues) so Carrie just comes off as... less interesting.
Still, her inclusion did seem to inspire Konami to continue using the Belandes clan in the future as later decendents (Charlotte Aulin and Yoko Belnades) picked up the torch from our young Fernandez down the road.
Castlevania (for the Nintendo 64)
At a young age Carrie was forced to watch as the forces of darkness killed her family in front of her eyes. That day Carrie swore she would fight the demons that stalked the night in a quest to seek vegeance for her fallen loved ones. When Dracula's castle appeared in the Romanian mountains, Carrie ventured the Dark Lord's lands. There she met up and joined forces with the Belmont decendent, Reinhardt Schneider, who was also on a quest to destroy Dracula.
The two heroes entered into the demon-populated lands, eventually gaining access to an old, abandoned villa. Within the ground Carrie met up with a young boy, Malus, who was running from the fiends of evil romaing the land. Carrie helped the boy escape although she had the feeling there was something... off about the lad. She then ventured further, getting into Dracula's castle itself soon after.
Within the castle, Carrie encountered the evil witch, Actrise, an evil sorceress who swore allegience to Dracula. In their early conflict, Actrise forced Carrie to fight another Fernandez woman, one who had wandered into the castle ground years before on her own quest to save the world only to be captured and turned into a vampire. Carrie fought the sad creature, eventually besting it and freeing the poor woman's soul.
Further explorations in the castle sent Carrie on a different path from Reinhardt into towers of science and magic before the two met up again. Nearing the top of the fortress Carrie once again confronted Actrise, this time doing battle directly with the evil witch. Carrie was victorius, sending the evil enchantress straight to hell while our heroine climbed ever higher in the castle.
It was at the top of the tower, after a battle with a false Dracula, that Carrie encounters Malus again. Here it was finally made clear that Malus was a vessel for Dracula's soul and was, in fact, the true Dracula. Carrie was forced to fight the newly resurrected Dark Lord in a pitched battle. She survived, defeating the foul demon, but sadly Malus was lost to the darkness, his soul wiped away by Dracula's evil.
Leaving the castle as it crumbled behind her, Carrie felt at peace having gained her vengeance. She visited her mother's grave one last time to share the news and to move on with her own life.
The Nintendo 64 Castlevania technically had multiple endings, good and bad, that despicted what happened to the heroes if the did or did not defeat the true Dracula (Malus). Of course, only the good endings are in continuity (largely because the bad ones depicted Malus still alive with the power of the Dark Lord within him, something that clearly never came to pass in the later games in the series). Not that continuity is easy to pinpoint with these games -- they hold a nebulous place in the series at best and, generally, are considered non-continuity titles at this point (not that we ever pay attention to pesky things like that here).
Technically Carrie shows up in two games but the latter, Legacy of Darkness, was considered a director's cut of a sort for the original title. That game featured a main quest starring a different hero, Cornell. Originally Cornell was slotted to show up in the first version of the game but was cut due to time constraints. His adventure was restored in Legacy and then Carrie's adventure was added in as an unlockable. Some minor things were changed (such as which levels were in the adventure) but the two versions are, more or less, the exact same game (with the exact same plot) so, as far as Carrie's history is concerned, they're the same title.
It's worth noting that although her last name in English is Fernandez, it's not entirely known if Carrie was supposed to be part of the Belnades clan directly or not. As some fans have pointed out, the Japanese translation of her name is (loosely) "Verunandesu" while the Japanese name for Sypha is also "Verunandesu". Even if the spelling is slightly different (hard for English speakers to note), the F and the V have similar noises when translated to Japanese, and the B and V are pracitcally the same noises in Spanish. Some have theorized that "Belnades" was originally supposed to be "Fernandez" but due to poor translation was garbled when it came over to Western shores. Likely Carrie is a proper member of the Belnades but (for all these reason) we segregate her out from the rest of the clan.
Playing as Carrie:
Considering the number of things that were rearranged and shuffled for the two titles as well as all the things that were cut in the first release, it no surprise that Carrie doesn't play much a normal Belnades. While she can shoot orbs of force as her primary attack, she doesn't do much else that the other Belnades woman can. Most specifically, Carrie doesn't have the three traditional Belnades spells established in Castlevania III -- ice, fire, and lightning -- instead using sub-weapons just like Reinhardt. This was obviously done for coding and/or space concerns (since Cornell and Henry use the same sub-weapons in their adventures in Legacy, too), but it would have been nice to have a little more variety.
Still, in many ways Carrie is the better choice to play as between her and Reinny. Her smaller size does seem to have a smaller hit-box to go with it, making her easier to play as. Coupled with her force orbs and the general usefulness of her close-quarters melee attack (arm rings), Carrie's quest ends up being much easier in many ways than her companion's.