I was reviewing some moments of Arrow's last week episode, "Restoration" and I noticed something that bugged me the first time but that I understood well after.
During the opening scene of the episode, Diggle and Oliver are on the field pursuing a team of Damian Darhk's Ghosts. While searching for them, Diggle got hit by one of the Ghosts and was about to get killed, but oddly instead of taking the shot the man hesitated and finally runaway.
Obviously, only one person could have reacted that way in the sight of Diggle:
From the start of Arrow, Andy's death always has been a burden on Diggle shoulders. And it became even more heavy when he find out that his brother had been killed by an organisation called H.I.V.E. Thus, with the arrival of Damian Darhk this subject will be even more important for him.
To go back to that scene, the focus the camera made successively on Diggle's then on the Ghost's face was weird. It was like they were trying to highlight something important.
Deadshot is not reputed to miss his targets and he certainly didn't but, Darhk possesses waters of the now gone Lazarus Pit and from there it's not hard to make the link. What better way to assure someone's commitment than reviving them.
I could imagine that Darhk built his entire organisation with skilled people resurrected thanks to the waters of the Pit. It's only easier covering your traces with an army that doesn't exist.
Clearly it's only speculation based on one scene for now but, all the magic that is starting to surround the show makes almost anything possible. And it would be something game-changing for Diggle, learning that his brother is working for the men who allegedly killed him.
I don't know if this theory will prove itself to be true but tell me what you think !
Arrow season 4 airs Wednesdays on The CW.