Thread:SasookayIsRlyCoo/@comment-27699640-20160708140221/@comment-24936031-20160710092625

He did it with his arm alone. In the image you're linking, it's part of the kakuja.

As for the development... um. The tentacles on his back are pointing in a different direction. He's using them to for the blades on his arm. That's about it. If anything, I think the swiss-army knife lizard hands are the bigger development. In fact, this page shows it transitioning between the image I uploaded and the current one http://readms.com/r/tokyo_ghoulre/076/3407/4. It just looks like he's utilizing it in a different manner (reptilian hands to sword hands). They both seem relevant.