<P> In season two, Oliver returns to Starling City after spending time at Lian Yu to work through his grief . He now goes by the alias "Arrow" and, in honor of Tommy, vows never to kill again . He fights criminals who take advantage of the Glades after its destruction, while trying to redeem himself as a hero, but is challenged when those closest to him are endangered . He co-administers Queen Consolidated with Isabel Rochev and becomes friends with Alderman Sebastian Blood . Oliver finds himself investigating a larger plot orchestrated by Slade Wilson, involving "Mirakuru", a strength - enhancing drug . It is Slade's intention to destroy everything and everyone Oliver cares for . Sebastian and Isabel are also working for Slade and help bankrupt Oliver, causing him to lose his home and business . Oliver gets help from Sara Lance, now the vigilante "Canary", and takes Thea's boyfriend, Roy Harper, as a protégé . After Felicity injects Slade with the Mirakuru cure, Oliver defeats Slade and locks him in an underground prison on Lian Yu . In flashbacks, Oliver is hunted by Dr. Ivo's armed crew who seek the Mirakuru and he accidentally causes the death of Shado, his lover on the island . Slade also loved Shado, which explains his vendetta against Oliver . A flashback before the shipwreck reveals that Oliver impregnated a college classmate named Samantha Clayton, and Moira paid Samantha to tell Oliver the child died and to move to Central City, leaving him unaware of his impending fatherhood . </P> <P> In season three, Oliver has become a public hero to the citizens of Starling City and has taken Roy on as a full sidekick . He lives in his foundry safe - house, having lost his mansion . Oliver is faced with the moral question of whether he can be Oliver Queen and live his life while the city needs the Arrow . This is further challenged when he realizes he is in love with Felicity . She has caught the attention of Ray Palmer, the new head of Queen Consolidated . After Thea returns to Starling City, they decide to reopen their nightclub together . Oliver is also inadvertently embroiled in a conflict with Raʾs al Ghul due to Malcolm's manipulations . During a fight with Raʾs, he suffers a mortal wound and nearly dies, but is saved by Maseo and Tatsu Yamashiro . Raʾs demands that Oliver become his heir because he is the only man to survive a death match against him, fulfilling a prophecy of the League of Assassins . When Oliver rejects the offer, Raʾs tries to force him by killing people while posing as the Arrow . When Raʾs nearly kills Thea, Oliver chooses to join the League, abandoning his former identity to become Al Sah - him (Arabic: سهم ‎; "Arrow"); he pretends to be a darker and crueler version of himself in order to get closer to Raʾs and destroy the League from within . Raʾs has Oliver marry his daughter, Nyssa al Ghul, to keep his bloodline in charge of the League . Oliver later kills Raʾs and inherits the mantle but immediately passes it to Malcolm . He decides to retire from being the Arrow and live with Felicity, knowing that Laurel, Diggle, Ray, and Thea will protect the city in his absence . The season flashbacks explore Oliver's time in Hong Kong where, after witnessing his combat capabilities on the island, Amanda Waller forces him to become an A.R.G.U.S. agent using the Yamashiros as his handlers . It is revealed that Oliver returned to Starling City while on a mission where he discovered Thea's drug problems,, witnessed the start of the relationship between Laurel and Tommy, and seeing John Diggle and Felicity Smoak for the first time . </P> <P> In season four, Oliver is called from retirement to help Laurel and Thea stop a group known as "The Ghosts" led by Damien Darhk, leader of H.I.V.E. Oliver now goes by the name "Green Arrow", ostensibly a new vigilante following in the footsteps of the Arrow, who Star City (formerly Starling City) believes to have died . He plans to propose to Felicity and run for mayor . While on a mission with Barry Allen in Central City, Oliver meets Samantha Clayton's son, William, and ultimately learns that he is William's father . Samantha refuses to grant Oliver full access because of his playboy past and her ill feelings toward his mother . The revelations of his fatherhood complicates Oliver's relationship with Felicity and his duty as Green Arrow, and threatens to jeopardize his mayoral campaign . When a H.I.V.E. attack leaves Felicity permanently paraplegic, Oliver's fight with Darhk becomes a vendetta . Oliver also discovers that Thea is dying because the Pit's restorative effect on her is waning; Nyssa offers a cure in exchange for killing Malcolm . In a fight, Oliver cuts off Malcolm's left hand and gives the Demon's Head ring to Nyssa in exchange for the cure . Nyssa disbands the League of Assassins, causing Malcolm to seek vengeance against Oliver . As a result, Darhk kidnaps William, Oliver's relationship with Felicity becomes estranged, and Oliver is forced to resign from his mayoral campaign . After Darhk is successfully prosecuted, Malcolm, with help from Andy Diggle, aids Darhk's escape by restoring his magic, and fatally stabs Laurel with Oliver's arrow . Laurel dies of her injuries moments after admitting that she still loves Oliver, who is devastated . During his quest to stop Darhk, Oliver learns that the pure forces of light can counter Darhk's powers and that H.I.V.E. plans to rule a post-apocalyptic world . At the end of the season Oliver stops Darhk's plan to destroy the world and kills him . With the death of the previous mayor, Ruve Adams, Oliver becomes acting mayor of Star City . The season's flashbacks explore Oliver's training with A.R.G.U.S. and his infiltration of the Shadowspire organization on Lian Yu . </P> <P> In season five, Oliver initially returns to killing because he blames himself for Laurel's death . He later recruits a team of vigilantes to help balance his double life as Green Arrow and Star City's mayor . In the process, he meets metahuman vigilante Dinah Drake, and sees her as a candidate to succeed Laurel as Black Canary, inspired to continue Laurel's legacy after encountering her evil Earth - 2 counterpart . Oliver is stalked by a mysterious archer, Prometheus, who seeks vengeance for the death of his father by "The Hood". The season's flashbacks examine Oliver's time in Russia, where he joins the Bratva (Russian mafia) as part of an assassination plot against Konstantin Kovar and explores the criminal fraternity in the process . One of Raʾs al Ghul's children, Talia al Ghul, trains Oliver and gives him green garb based on the League of Assassin's uniforms . In the present, Talia seeks vengeance against Oliver for killing her father and allies with Prometheus, who was another of her students . After a series of battles with Prometheus, leading to the abductions of Oliver's family and friends, including Samantha and William, Oliver defeats his enemy at Lian Yu, though Prometheus kills himself afterward . William also learns of his relation to Oliver and discovers his father's secrets . </P>

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