The Castlevania franchise has been prolific on Nintendo's handhelds, with six titles evenly split between Game Boy Advance and DS. It wouldn't be too much of a surprise if Konami was planning a new entry for the series on 3DS, and in typical pre-E3 fashion a rumour has emerged online.
The story has appeared on Dutch website n1ntendo.nl, which admits that it knows little about whether Castlevania: Mirror of Faith would be a 2D title like its handheld predecessors, or a 3D adventure. It's claimed that Castlevania: Lords of Shadow producer David Cox, of Spanish studio MercurySteam, is working on the project. There have been rumours in the past of a follow-up to the Xbox 360 and PS3 title, though whether a potential offering on 3DS would be a sequel or spin-off — either in a 2D or 3D style — is up for debate.
Although it's only a rumour, there appears to have been some interesting back and forth between n1ntendo.nl and Konami. After first publishing the story it was then taken down, with the site claiming that Konami had requested that it go offline due to inaccuracies in the reported name and an upcoming E3 announcement. The site has now re-posted the story claiming that its initial report was correct and is choosing to ignore Konami, based on finding some registered web URLs supporting the fact that the project could be called Mirror of Fate, after all.
If it's true that Konami attempted to stop the story for fear of spoiling an E3 reveal then this rumour may have some merit, though we still suggest taking it with a pinch of salt.