Arrow Season 4 shocked and delighted DC fans with news that Warner Bros. had actually approved Matt Ryan‘s now-canceled Constantine to crop up in Starling City for a crossover, many speculating what would bring the demon-fighter into Oliver Queen’s world. Now, new details confirm that Constantine will have a hand in Sara Lance’s pre-Legends resurrection, among other surprises.

Where previously we’d learned that Arrow Season 4 would cover Sara’s White Canary resurrection prior to the character’s arrival on Legends of Tomorrow, TVInsider had executive producer Marc Guggenheim elaborating on Constantine’s mystical expertise. In particular, Season 4's expanded focus on magic will precipitate fifth episode “Haunted,” dealing directly with the side-effects of Sara’s dip in a Lazarus Pit:

Each year on the show, we have added and expanded the mythology with different elements. In Season 2 we introduced the idea of superpowers, last year brought in the League of Assassins, and for Season 4, we always had a plan to introduce magic and mysticism. We were already swimming in those [Lazarus Pit] waters and that’s why Constantine is this great organic little development.”

Unlike Thea, who wasn’t fully dead, the consequences of using the pit on someone as dead as Sara was creates some unforeseen difficulties…and John Constantine is uniquely suited to help our team deal with those.

In addition to Guggenheim previewing that Matt Ryan would don the same wardrobe as the defunct NBC series, IGN’s own conversation with co-showrunner Wendy Mericle went a bit further, suggesting that Matt Ryan’s appearance would retroactively link the two universes (already including Flash‘s) into one:

Absolutely. He is coming in fully as who he was on the show. We’re getting wardrobe. We’re very excited to have him. He’s a tremendous actor. It’s so cool to have that cross-pollination. We are very lucky and DC was very generous letting us have him.

Elsewhere of Arrow Season 4, we know the fourth year is expected to somewhat creatively revamp the series after its Season 3 finale saw Oliver retiring the vigilante lifestyle (at least with his current costume). In addition to a focusing on DC villains H.I.V.E. and Damien Darhk (Neal McDonough), Season 4 will also introduce Rutina Wesley, Parker Young, Jeri Ryan’s Jessica Danforth, J.R. Bourne’s Double Down, Echo Kellum’s Mr. Terrific, and Alexander Calvert’s Anarky. Apart from Wendy Mericle’s elevation to co-showrunner alongside Marc Guggenheim, we also know that Punisher: War Zone director Lexi Alexander will helm an episode.

Arrow Season 4 will premiere on October 7, but will Constantine’s appearance do justice to Sara’s Legend-ary resurrection?

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