The shadow power had always been a great defensive measure, and while Quinn continued to grow so did his shadow powers. They only got better in terms of defence and the things it could do.
There was the shadow infect skill but that still wasn't really an offensive skill either. In order to try to make the shadow more versatile in battle, Quinn had attempted to fuse it with his Qi. This had worked, giving it a solid form.
The only thing was, this only allowed it to still be used in a defensive way, and to grab onto or hold things better. It could be used to attack in this form but it was weak, and it was better for Quinn to use his Qi in a physical way or with his vampire aura if that was the case.
So, what about his blood aura, mixing it with the shadow. For the longest time, Quinn thought that this might be impossible because of the trait of the shadow itself. It was meant to block everything out and slow things down from the original way they worked.