Quote Originally Posted by DarthEnderX View Post
He's also be working in conjunction with other devils. There's already been 3 working with him we know of.
I feel like the devils that had been powered up by pieces of the Gun Devil weren't working with the Gun Devil. I would go as far as saying they were random devils the Gun Devil powered up for no particular reason or for experimentation. The Gun Devil is so strong it can afford to do it. If it can track its own body parts later, like you suggested, then it could have also counted on those devils being defeated by the agency, which would allow it to see where those body parts end up to.