Colton Haynes will return as Roy "Arsenal" Harper in Arrow Season 7, and his castmates couldn't be happier about it. At Comic-Con International in San Diego, his co-stars Stephen Amell, Juliana Harkavy and Rick Gonzalez praised Haynes and teased a new, exciting role for his character.

"It's fantastic, man! I love Colton! So having him back is terrific, and -- you know -- his stuff this season? I could give you an hour to guess, to pontificate as to what he's going to be doing, and none of you would get it. It's amazing," Amell shared.

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"Just as far as the overall feel on set, it's been great, because everyone loves Colton," Harkavy added. "I think everybody really missed him, so it feels more like a family with him and it feels more complete with him."

"I'm excited to see the fans to see Colton back! Colton's back!" Gonzalez pitched in.

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News of Haynes' return broke in April. The Teen Wolf star was a series regular on Arrow's first three seasons before he decided to step away from the role. Nevertheless, he returned for one- and two-episode guest spots in Seasons 4, 5 and 6. His two-episode Season 6 arc ended with him riding off into the night with Thea to help her right her father’s wrongs. At this time, it is unclear what will bring Roy back into the fold for Season 7. However, it likely means that his relationship with Thea Queen — which was rekindled in Season 6 — has come to an end, since Thea actor Willa Holland has exited the series.

Premiering Monday, October 15 at 8 pm ET on The CW, Arrow Season 7 stars Stephen Amell as Oliver Queen, David Ramsey as John Diggle, Emily Bett Rickards as Felicity Smoak, Rick Gonzalez as Wild Dog, Echo Kellum as Mr. Terrific, Juliana Harkavy as Black Canary and Katie Cassidy as Black Siren.