Isabel Rochev (Summer Glau) returns for "Deathstroke," as she intends to take Queen Consolidated away from Oliver.
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Despite the cuffs, Slade makes his move against Oliver on Arrow. "Deathstroke" is the 18th episode of the show's second season.
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Arrow Season 2 Episode 18 Quotes

Oliver: They're calling you Deathstroke.
Slade: That's a bit flamboyant. I like it.

Well, I told a guy the truth and he got struck by lightening. To be fair, it probably won't happen again. Statistically.

Felicity