Wait, about the scar thing, what about Mikhail ? I know we haven't seen his bare-chest but the way his core crystal is integrated into his design, and what we saw of the experiment in his flashback, I don't think it would leave a scar.

Now my only question is who the hell is Taion ( and who's he descended from ? ) if he's an actual blade-eater ? Surely after Amalthus there would be no further use for that technology since it was used for him to fuse himself with a bunch of crystals. Unless some praetorian dude thought he could take it back up and redid the experiments ( would it even work without cleansing ? would it work without being an Aegis driver ?? )...

Maybe