It's said on multiple pages that Blade and the Butterfly Effect got their Septimas from Gunvolt and Joule respectively. Is there somewhere where this is stated?
It's stated in the Luminious Avenger iX OST booklet Asimov extracted the septimal inducers from Gunvolt's and Joule's bodies after having killed them. He would then go to implant them into Blade and Mytyl aka the Butterfly Effect.