[Warning: This story contains major spoilers from Wednesday's episode of Arrow. Read at your own risk!]

Slade Wilson's dastardly plan claimed yet another life during Wednesday's episode of Arrow but this time, there was a twist!

After Oliver (Stephen Amell) ...

[Warning: This story contains major spoilers from Wednesday's episode of Arrow. Read at your own risk!]

Slade Wilson's dastardly plan claimed yet another life during Wednesday's episode of Arrow - but this time, there was a twist!

After Oliver (Stephen Amell) tracked down the stolen S.T.A.R. labs machine, which was being used on Roy (Colton Haynes) to filter the Mirakuru in his blood to the prisoners that Slade (Manu Bennett) recently set free, the emerald archer faced off against both Slade and Isabel (Summer Glau). But Diggle (David Ramsey) made short work of Isabel, shooting her in the chest.

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Isabel is far from dead, however. In the closing moments of the episode, we learned that Slade gave her some of his blood so the miracle drug could save her - and make her practically invincible. "Now that she's got the evil juice in her, as we call it in the writers' room, she's Ravager," executive producer Andrew Kreisberg says, referring to the DC Comics villain whose arrival ended up being one of Arrow's worst-kept secrets after Glau was photographed in costume earlier this month.

In the comics, the alter ego eventually belongs to Rose Wilson, Slade's illegitimate daughter who he brainwashes into becoming his apprentice. However, Isabel is definitely not Rose Wilson, since the producers decided to go in a different direction. In fact, they originally had other plans for Ravager. "Isabel was the one thing we weren't entirely sure about as we were developing the season," Kreisberg says. "Truthfully, there was a very early iteration of the series where Sara [Caity Lotz] started the season as Ravager, and then we switched over."

Even after the role was envisioned for Glau, the producers initially planned to keep her board room-esque character quite tame compared to the tough-gal characters Glau played on Firefly and Terminator: The Sarah Connor Chronicles. "When Summer took the part, I was up there on set with her and she's like, 'I've never done anything like this. I feel much better if I'm kicking somebody,'" Kreisberg says. "And I was like, 'You're so good, you should give yourself more credit. We wanted you because you're a good actress and you're amazing in this part, not because you can kick a--.' Then I got to call her and go, 'Hey, we changed our minds, you get to kick a--.'"

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"Part of the reason Isabel disappeared for a while is because we still weren't quite sure which way to go, whether she should be an ally or a villain," he continues. "We had written it so that it could turn out either way. The scene that I was picturing was Isabel, Slade and Sebastian [Kevin Alejandro] in Oliver's office, the triumvirate of evil. Once that happened, there was no way she was not going to be Ravager."

Were you surprised by the reveal that Isabel is Ravager? Hit the comments!

Arrow airs Wednesdays at 8/7c on The CW.

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View original Arrow Boss on Big Ravager Reveal - And Who Almost Played Her! at TVGuide.com

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Other Links From TVGuide.com FireflyDavid RamseySummer GlauAndrew KreisbergKevin AlejandroStephen AmellTerminator: The Sarah Connor ChroniclesManu BennettColton HaynesCaity LotzArrow

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