Board Thread:Rebirth: Applications/@comment-25152698-20141025195406/@comment-1875854-20141105222527

No, I don't believe Magnet Release itself is just advanced lightning. That would also take years of specialization, reason why it is S rank for him, in order to magnify the magnetism that lightning natural emits, because the two are related. But the actual release itself is still a KG, and Kei doesn't exactly use magnet release. I classified it as the same because it does the same thing almost, but it comes from the properties lightning has already.

And then you could say Sayuri's release is somewhat different from traditional metal release. This is basically still metal, just using it in a different form. No need to add weird natures, just state that's how she uses metal uniquely, dubbing it Metroid if you wish.