Sylphie (シルフィー Shirufī ) is a supporting character in the 1988 Arcade shoot 'em up Forgotten Worlds, serving as the in-game shop owner. She is named Mirabella in the English manual for the Sega Genesis/Mega Drive port and Lucia in the manual of the Master System version, and her name was transliterated Sylphy in the English PC Engine port's manual.
Sylphie is a mysterious merchant with unknown background and motives. She appears to have some unique abilities, being able to appear and disappear instantly as if carried by the winds. She's the sole owner and manager of Sylphie's Store (シルフィーの店 Shirufī no Mise ), a miraculous store that is capable of rising out of any surface or area regardless of location or danger when needed the most by her customers.
Sylphie approaches the two Unknown Soldiers as they observe the desolation of Dust World from a mountainside, begging them to save this world from Bios and asking them to restore hope to those who have lost it, becoming the "people's hope". The Unknown Soldiers showed intent to take up her plea but didn't know where to start, then she exclaimed she was certain they had the power to stop Bios. At the moment a gust of wind enveloped them and, when the soldiers opened their eyes, Sylphie was nowhere to be seen, leaving only her voice echoing in the two soldiers' heads.
During the game, Sylphie's Store appears on specific points in the stages, rising out of the walls/ceiling. If the player enters them, they will be able to buy different weapons, satellite options, items and information about the bosses for a cost of zenny. After Bios' defeat, she will appear to the Unknown Soldiers and thanks them, assuring peace will once again return and that the people will rebuild their cities no matter how long it takes.
- Sylphie appears as an INN owner in Adventure Quiz: Capcom World 2 and Capcom Quiz: Hatena? no Daibouken.
- Sylphie, along with the Unknown Soldiers, appear in Namco × Capcom, where she attacks with a number of weapons, attacks and costumes from other Capcom games, such as Michelle Heart, the pistols from Gun.Smoke, and Jin Saotome's Blodia Punch. This incarnation established her extreme merchant-oriented personality and zeal to sell her goods to anyone in either side of the conflict.
- Sylphie returns as one of three shop owners in Project × Zone 2. As part of a gag in the English version, Sylphie introduces herself as Mirabella, her localized name in the Sega Genesis port, only to change it to Sylphie at the end of the chapter as she thinks the name to be more marketable.
- SNK vs. Capcom: Card Fighters Clash has a shop based on Forgotten Worlds, containing a giant Dust Dragon statue and a character named after the game, as well as Sylphie acting as a card seller in a shop that appears and disappears just like her shop in Forgotten Worlds.
- In the Japanese version of the game, Sylphie has an animation in which she bows to the player when her shop is entered, and she has vocals for most of the lines she speaks while in her shop. Both these elements were removed from the English localization for unknown reasons.
- In the final stage's 2nd store Sylphie offers an unique item known as Dress, which is her own dress. This is exclusive of the Japanese version, with the English game replacing it with a Flying Stone. The item is the most expensive in the game (99900 Z) and when purchased, Sylphie will say "You're very naughty" (あなたってとってもHなのね Anatatte tottemo Ecchi na no ne ). The item doesn't have any inmediate effect, instead granting a bonus 2.000.000 points upon beating Bios. The item is infamous among fans of the game for the fake theories it spawned about a secret way to have Sylphie undress in-game, and as a result the item and Sylphie's line have made their way into both Namco × Capcom and Project × Zone 2, becoming an end-game high level armor equipment.
- In Street Fighter Alpha 2, there's a clothing store in the background of Guy's stage named "SILFIES Wardobre 1988". The name is a misronamization of Sylphie's name, the year 1988 is Forgotten Worlds release date and this being a clothing store is likely a nod to Sylphie's "dress" item.