Following the months and months of criticism from haters of "Olicity," Oliver (Stephen Amell) and Felicity (Emily Bett Rickards) broke up in Season 4 Episode 15 of "Arrow," aired Wednesday, March 2. However, there are more pressing matters Oliver and Team Arrow must deal with in Star City, but they will not get to that until March 23, when "Broken Hearts" will be aired.
Fans have been waiting desperately to know who is in the grave, and one by one they have been able to strike off one beloved character after another from the list of top contenders. As of now, we know Felicity and Oliver's son are safe from being killed off in the upcoming episodes. Considering William and his mother's story-line was wrapped up, at least temporarily, in "Taken," it is unlikely for them to even return to the show this season.
Thea (Willa Howard), who recently had a near-death experience, is also most possibly off limits. She has had a very strong story-line this season, and cheated death once. It would all be for nothing if she were to be killed just a few episodes after that.
Those who watch "Legends of Tomorrow" know the gang travelled to Star City of 2046 in Episode 6, and ran into the new Green Arrow, aka Connor Hawke aka John Diggle Jr (Joseph David-Jones), who is Diggle's (David Ramsey) son. In the episode, Connor had said his father died when Deathstroke's (Jamie Andrew Cutler) terrorism gained ground.
This clarifies that in this particular timeline, Diggle was around until approaximately 2030, a timeline which spares Diggle the grave in Season 4.
The three remaining characters whose death would have a serious impact on Oliver and Felicity are Laurel (Katie Cassidy), Quentin Lance (Paul Blackthorne) and Donna Smoak (Charlotte Ross). The prophecy of death for these characters is supported by the set photos recently circulated online.
The photos, said to be from a future episode with flashback scenes, show Laurel and Quentin in a graveyard. A coffin is seen being carried by a group of men, one of whom looks like Stephen Amell. Also seen on the sets are Nyssa (Katrina Law) and Dinah Lance (Alex Kingston).
Quentin has been a strong possible choice for the person in the grave since the beginning, and now, it looks like that theory may have been right all along. However, the possibility of Donna's death cannot be counted out.
In "Taken," Oliver had made the choice of keeping his son and baby mama at a distance so they would be safe, whereas, when given the same choice, Quentin had decided to keep Donna close and tell her the truth about his association with Darhk (Neal McDonough).
Quentin not only worked with the bad guys, he also double-crossed them. That is "Cause of Death 101" in the comic-book universe. Considering it's a TV Show, they may also give Quentin a greater punishment by killing someone he loves, aka Donna.