I have this feeling that we might see Amanda Westfield return in the sixth season of Arrow going after Oliver and his team since she blames them for her son's demise as well as hating Oliver for putting an arrow in Justin Claybourne since he is the father of her child. I feel that because Stephen Amell said that the theme this season is about family meaning that we might get to see flashbacks of how Simon Morrison AKA Adrian Chase AKA Prometheus grew up with her.
Also as another confirmed plotline, in keeping with the season’s found-family theme, a "villainous cabal" rather than a single foe will torment Oliver and Team Arrow throughout the season". I can see Amanda being wanting to torment Oliver and Team Arrow since she blames for everything. When she first appeared in "The Sin-Eater", she appeared to be a nice lady until her darkness was revealed after learning of how her son was going to be imprisoned for potentially being the Throwing Star Killer. It appears that she will always be on her son's side no matter what happens, even if it involves him killing innocent people. Later on when Team Arrow came looking for Amanda, they discovered that Adrian had her mother moved. During this time, I bet Adrian told his mother every thing about how the Hood, Oliver Queen, and the Green Arrow are the same person, the existance of The List that provves Justin Claybourne had ties to Malcolm Merlyn while making a contribution to the Undertaking or risk his illegal activities being exposed to the public, and more about Oliver's past including his activities on Lian Yu, in Hong Kong, and Russia. He probably reveals to her mother more about Oliver's son, about the Legends, Team Flash, time travel, and the multiverse. I think Amanda would use that information to then go after Team Arrow by hiring assassins to go after them by using Justin Claybourne's money. I can see her hiring villains such as Ricardo Diaz Jr., Jeremy Down, Sports Master (who is revealed to be a relative of Evelyn Sharp. I got the idea because of him being Artemis' father in Young Justice), Cheshire, and Onamatopeia.
Eventually, Oliver, who is angry that Adrian caused the death of Samantha Clayton and endangered his son William, makes Amanda feel responsible for Adrian's death. When I did my research on Adrian Chase, I discovered that he had no disregard for his life and that would make Amanda feel guilty for not accepting Oliver's offer in the first place to give her son help as the mayor of Star City. Oliver would also reveal to Amanda about how Claybourne was planning to disown Adrian. I bet that would cause a lot of drama and I wonder how Amanda Westfield would react to this knowledge.
In the sixth season of Arrow, they announced how they're introducing Samandra Watson as a no-nonsense FBI agent tasked with investigating Oliver Queen's connection to the Green Arrow. I think the FBI wants to bring down the Green Arrow because they deduced that he and another archer helped Adrian Chase escape while being unaware that Oliver had no choice since Adrian had his son hostage. Samandra Watson would first deduce that Amanda Westfield is the Throwing Star Killer's mother and confront him. Amanda then realizes her son is dead since he didn't come into contact with her as promised and immediately plots her revenge on the Green Arrow. Like Prometheus not wanting Tobias Church to kill the Green Arrow since he wants Green Arrow to be alive to make him suffer, Amanda refuses to allow anyone to kill the Green Arrow since she wants Oliver's blood to be on her hands which is why she kills Watson. This would be a lot like Dexter where Lila kills Doakes after Doakes realizes that Dexter is the Bay Harbor Butcher. She could organize the hit on the rest of Oliver's team and pay extra to have the Green Arrow captured only so she can kill him.
Do you guys think that Mama Prometheus would make a terrific villain for the sixth season of Arrow? Let me know.