'Arrow': Oliver Gets Big League Boost in Season-Finale Battle (Photo)

The May 14 closer pits Oliver and friends against Slade's Mirakuru army -- and Oliver may have an edge.
Cate Cameron/The CW

[WARNING: Spoilers ahead for Arrow's season-two finale, "Unthinkable"]

With only three episodes left, Arrow is upping the ante with the return of a familiar face.

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After the shocking death of Moira Queen, Slade Wilson has Oliver Queen's number, vowing to kill one more person from Oliver's life. Thankfully, Oliver will be getting some much-needed help, due mostly to Sara Lance (Caity Lotz), who left town at the end of last week's episode "to go get help," said executive producer Andrew Kreisberg, "because when you're fighting an army you need an army."

As the image from the May 14 season-two finale reveals, one of those allies Sara brings back to assist in the Slade vs. Oliver war is none other than the League of Assassins' Nyssa al Ghul, played by Katrina Law. (Nyssa's eventual return was teased earlier this year.) Seen here with one of her assassins, Nyssa -- who viewers last saw in episode 13, "Heir to the Demon," in February -- will play a significant role in the season-ending fight, which sees Arrow, Canary, Roy and the League going up against Slade and his Mirakuru army for Starling City.

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Just how brutal will the final fight be? Consider this a warning: "The finale is f---ing insane," Kreisberg said.

Other familiar faces popping up in the final episode include Celina Jade, who plays Shado, and Cynthia Addai-Robinson, who plays Amanda Waller.

Arrow airs Wednesdays at 8 p.m. on The CW.

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