It's no secret that Manu Bennet (Arrow's Deathstroke) is not a fan of the show's third season. Previously stating that he feels the writers "took the character in the wrong direction" and saying that Thea beating Slade in Season 3 was just "a beating of Slade" and that it "added insult to the injury".
Now Manu seems to have agreed with a (pretty funny) fan comment about how the Arrow writers (cough*Marc Guggenheim*cough) would make Felicity beat Slade and that he should stay away from the show, as you can see below. This seems to be the nail in the coffin, and bad new for fan's of Bennet's character (everyone who watches Arrow). As a fan I would love for Deathstroke to return to Arrow for Season 4, as he is to me and many other fans, the best part about the show, but it seems that that's just not going to happen. I wonder if this rules out apperances on The Flash as well ?