Throughout Season 5 of "Arrow," the mysterious Prometheus has made life miserable for Oliver (Stephen Amell) and his team. While the true identity of Prometheus remains a secret he guards closely, his tactics couldn't be anymore clear.

This is someone who thrives on manipulating and tormenting his target -- in this case the Green Arrow -- to the point of madness. It was in the midseason finale that his games led to Oliver killing Felicity's (Emily Bett Rickards) boyfriend, which is something the whole team will have to live with forever.

It's these mental games that makes Prometheus stand out -- and for executive producer Wendy Mericle, that's a big part of the reason why the character is so important to the show and why their Prometheus is a complete departure from the villain of the same name in the comics.

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"Part of the fun of that is that you can draw on other sources of inspiration," she told us during a group interview -- and while those inspirations may come as a surprise, looking back on the story so far, you can see the fingerprints of a number of notorious movie villains.

"One of the things we talked a lot about was 'American Psycho,'" Mericle recalls. "We talked about who are the big manipulators? People like Hannibal Lecter and Kevin Spacey's character in 'The Usual Suspects' and also in 'Seven.' We talked a lot about those types of villains, and how to bring that element into the series -- because we were looking for something different to do in Season 5, a way to change it up and make it different."

The fact that "Arrow" can still strive to be different in that way, especially when getting back to its roots after a mysticism-infused Season 4, is remarkable. If you look back on Damien Darhk (Neal McDonough), the fight he brought to Team Arrow was so vicious and over-the-top that it was hard to think of anyone matching that intensity again. In creating someone as personal and manipulative as Prometheus though, they've done just that.

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His fight isn't about domination or grasping at power. It's about tormenting Oliver until he reaches his very breaking point. That's a scary foe to be up against.

"Arrow" airs Wednesdays at 9 p.m. ET/PT on The CW.

Posted by:Chris E. Hayner

Chris E. Hayner is equal parts nerd, crazy person and coffee. He watches too much TV, knows more about pro wrestling than you do and remembers every single show from the TGIF lineup. You may have seen him as a pro-shark protester in "Sharknado 3." His eventual memoir will be called "You're Wrong, Here's Why..." TV words to live by: "I'm a firm believer that sometimes it's right to do the wrong thing."