Arrow has been quite an emotional rollercoaster in the five seasons it's been on the air at the CW. Stephen Amell has garnered a large following, helping to revamp things in the wake of Smallville. Superhero shows such as The Flash, Legends of Tomorrow and Supergirl followed suit, but it's clear they have a long way to go before establishing the dominance that Arrow has held on the airwaves. It's always been about Oliver Queen experiencing pain, loss and subterfuge as part of his journey from being a billionaire-gone-missing to a fighter who emerged from the grips of death as a warrior of justice.

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With so many twists, turns and murders, the series has had quite a turnover in terms of characters, but it's always managed to throw in elements of humor and romance to ensure the audience remains sated. Arrow has diverse tones, but at day's end, it's an action series at heart about vigilantes, assassins and the war for the soul of mankind, which begs for more DC Comics characters to enter the fray. This has ramped up especially as the DCEU is yet to call him up to the DCEU filmverse, so with that in mind, CBR looks at 15 faces we'd love to see in Season 6!

SPOILER WARNING: Potential spoilers ahead for all seasons of Arrow

15 JERICHO

Jericho was hinted at big time when Oliver shared information on his whereabouts to convince Deathstroke to help him in last season's finale. Fans are definitely hoping that Slade Wilson's son does appear and, if so, that he comes packing his power to literally possess other people's bodies, or at the very least, mental persuasion, akin to the books. It would be quite a twist if he was actually a metahuman here, which could shape Slade as an anti-hero now trying to rescue him.

In the non-canon tie-in novel Arrow: Vengeance, Slade accidentally shot and killed Jericho, but now it's clear that Arrow's ready to shake up their spin on Deathstroke, so what better way to do so than by adding some family drama to the equation? This could even sew seeds for a crossover when Titans hits the air.

14 RICHARD DRAGON

Richard Dragon is another of DC's top martial artists, with many calling him their equivalent of Marvel's Shang Chi. He's had a storied past in the comics, training or fighting alongside the likes of Bronze Tiger, the Question, Huntress, Lady Shiva and recently, John Diggle. In fact, in the New 52, he pushed Ollie and Diggle to their limits!

He'd be a great addition here as he could be tied into Bronze Tiger's (Michael Jai White) appearance on the show, as well as that of China White (played by Kelly Hu). The writers could make him a hero or a villain, but what would be interesting is that whichever route they go with, Green Arrow will end up finding out that there are so many potential assassins still roaming around outside the al Ghul's League of Assassins.

13 HARPER ROW (BLUEBIRD)

harper row final

Harper Row was created by Scott Snyder and Greg Capullo in order to lead the new sidekick movement for Batman. Snyder wove her history (and her brother's as well) into Batman's, who saved their lives and eventually aligned with the tech-savvy Harper (under the new identity of Bluebird). Batman eventually showed her a lot of trust, especially as her mother's death was tied to Cassandra Cain's assassination endeavors.

Arrow often borrows from the Batman mythos, so why not use Harper here? It'll doesn't seem as if the DCEU will enlist this new breed of Bat-characters anytime soon, so maybe the writers can retcon her here from a technical person who's good with gadgets into something more pertinent to Ollie's universe. The mysterious hacker group Helix would also be perfect as they may be returning next season, and she could even act as an Oracle substitute serving with or against them.

12 LADY SHIVA

Lady Shiva stands ready and awaits her opponent's next move.

Lady Shiva would be a great figure to introduce into the Arrowverse because of her nature as one of DC's most badass assassins. She would fit in perfectly in a world featuring Deathstroke and the al Ghul family. Ironically, Katrina Law thought she was auditioning for this character only to end up getting the role of Nyssa al Ghul.

Shiva's past training of other assassins could also be a great focal point allowing her to clash with Oliver's team. She loves playing both sides of the coin and could even spark an arc with her daughter, Cassandra Cain. Team Arrow usually thinks that they've seen it all when it comes to stone-cold killers, but throwing such a lethal fighter into the mix could really provide Oliver's squad a bit of competition unlike any other, while offering us great fan service.

11 BLACK SPIDER

The Eric Needham version of Black Spider appeared in Young Justice and most notably, in the animated Batman: Assault on Arkham feature. He'd be perfect for Arrow as a ruthless vigilante, waging a war on drug lords, perhaps offering an Arsenal tie-in; or as a reluctant offshoot of Amanda Waller's defunct Suicide Squad.

It would be intriguing for Green Arrow to meet up with him because more often than not, Black Spider finds himself in murderous territory a la the Red Hood and could indeed remind Ollie of the dangers of crossing the line. Even as a villain, Spider still believes that there's a bigger picture here that transcends these evil schemers. This showed when he was a double-agent for the group known as Basilisk, proving that you can't trust him no matter which side of the fence he's on.

10 VIC SAGE (THE QUESTION)

Vic Sage becomes DC's The Question

Fans of the Justice League Unlimited cartoon got their fill of Vic Sage helping out the heroes through his investigative methods. Arrow would do well with such a detective, adding a bit more mystery to the show. They've already had Hub City (his home) on display and Marc Guggenheim has stated in the past that they'd love to write him in. With Renee Montoya (who also became the Question) in limbo over at Fox on Gotham, the CW should capitalize.

Rather than the convoluted Trinity of Sin or Suicide Squad angle, he could simply be reduced to someone trying to find out more about vigilantes, metahumans, Team Arrow in general, or end up simply aiding the heroes. He would be a great ally to Felicity, given how they both love the truth and fixing problems.

9 THE PHANTOM STRANGER

The Phantom Stranger would be a left-field pick to bring into the Arrowverse, but it would surely get comic fans tuning in even more. His DC characterization has been strongly linked to biblical origins, with the New 52 depicting him as Judas Iscariot, wandering for the rest of his days, and entrenched in the battle between Heaven and Hell. Arrow doesn't have to go that extreme, but they could work him in and bring back Matt Ryan as Constantine on the side as well.

There's potential for another mystical-themed episode as a break from all the violence and science, and perhaps we can see Oliver investigating the occult, looking for a sane solution to immortality outside of the Lazarus Pit. There were many casualties over the course of the series, so the Phantom Stranger could be the one to ward Green Arrow off such a search.

8 EL DIABLO

Diablo

El Diablo was one of the best parts of David Ayer's Suicide Squad, using his fire-manipulation powers to stave off the Enchantress. Arrow could easily do a television take on him as an excommunicated member of their own Suicide Squad or even as a decommissioned Checkmate hitman, who's now gunning for Team Arrow.

The Chato Santana version of the character would be the best bet, as seen on film, because he's an ex-criminal and can bring in ties such as gangs and being used as a weapon against his will. This may even offer up a potential arc of redemption with Oliver and, who knows, maybe Green Arrow can convince him to leave the past behind and be an ally to them. It's not like the character has much of a movie future anyway.

7 FRANKENSTEIN

Frankenstein

A little more horror wouldn't hurt the series. Frankenstein has been integral to books like Agent of S.H.A.D.E., Grant Morrison's Seven Soldiers, his own solo book, as well as Justice League Dark. Created by Victor Frankenstein, this immortal monster was made from body parts using varying sources, shaping itself as an undead, unstoppable behemoth. Imagine seeing him rocking his sword (allegedly that of the archangel, Michael's) and a pistol (akin to Hellboy)!

Given Frankenstein’s superhuman strength and the fact that he can keep on going even if he's being sliced up or shot up, he could flip Team Arrow's belief on its very head. Felicity's idea about science and mysticism would surely need some rethinking if they ever meet this creature, because Frankenstein is a myth that can certainly be just as big as the Batman.

6 ONOMATOPOEIA

Onomatopoeia mimics the sound of a fire.

Onomatopoeia was created by Kevin Smith and Phil Hester in 2002 for their Green Arrow run and he was used since as an assassin who's had it in for Oliver and his family. He loves using all kinds of weapons, including sniper rifles, knives and explosives, which could make him a Deathstroke or Anarky substitute if they ever need one.

He was actually supposed to have been used in 2013, but Smith discouraged the writers from adapting him as he felt it wouldn't be done justice on television. They went with J. August Richards' depiction of Mr. Blank instead. Regardless, this character remains a hitman that fans would love to see because he had such a good rivalry with Oliver. They may not even need to call him by name because his mask is so iconic.

5 ICON

Icon is an alien living on Earth, with a background and mode of operation similar to the Martian Manhunter's. He eventually enlisted a tech-savvy sidekick, Rocket, and both were seen on Young Justice recently. We already saw Martian Manhunter on Supergirl, so it's not that far-fetched for Arrow to continue with the alien arc from last season (which crossed over with Flash and Supergirl).

He always fought against injustice in the comics and, as a black hero, the CW could further expand the diversity within their television ranks. Icon has also shown a lot of love for humanity and it would be enjoyable to explore an alien's dynamic as part of Team Arrow. It would be even more awesome seeing a Milestone Comics character come to the live-action world as well.

4 TERRA

We recently saw Terra in Teen Titans: The Judas Contract where she betrayed the young superheroes and then sided with Deathstroke. It stuck close to the comic storyline where she was a mole in the team. But in the live-action world, rather than perishing, the CW should insert her as one of Deathstroke's secret weapons.

Any relationship with the Titans could even crossover to that series, but here, having her as a straight-up ally of Slade's could see him on his new path, on a quest to find his kids or even trying to reform his ways. Or he and Terra could simply start a new life as partners-in-crime. As long as she isn't too young and their relationship isn't creepy, then we'd love to see him mentoring her as the next wave of assassin.

3 STATIC

static-injustice-header

The Static Shock cartoon had a cult following as it relayed the story of Virgil Hawkins from Milestone Comics. He was a teenage superhero with electrical powers and, given the sociopolitical state of America, coupled with his story of poverty, now's a great time to see things from the perspective of a young black kid trying to fight for justice.

Fans already missed out on him in the Injustice 2 game, so hopefully the CW follows up on his appearances in Young Justice. Maybe it could be similar to the runaways arc seen in that cartoon where he's either part of a group of young metahumans who were experimented on or leading the search to find them so that they’re not exploited as child soldiers. This would make a great child-trafficking angle for Team Arrow to traverse and maybe even cross over with Black Lightning.

2 JIM CORRIGAN

Jim Corrigan would be a great addition to Arrow, in a similar fashion to how Jim Gordon polices Gotham at Fox. We already saw him in the DC Showcase: The Spectre short film and here, we could expand on him as this all-powerful mystical entity who is literally the Spirit of Vengeance. Emmett Scanlan played Jim, a cop from New Orleans, in Constantine, so he could easily be transposed to the CW and fully embrace his destiny as the Spectre.

If the showrunners decide they need to do away with Quentin Lance, as the destruction of Lian Yu may hint at, then Corrigan would be a great replacement, coming in to make a call on the vigilantes and big-time crime the series prides itself on. Corrigan has been a big staple in the comics, and could once more up the otherworldly aura of this series.

1 CASSANDRA CAIN

3 Cassandra Cain

If we can't get Batgirl (as Joss Whedon is making her solo flick), then we hope Arrow can bring another vigilante and former Batgirl to the table in the form of Cassandra Cain. She was molded as a warrior her entire life, and with assassins like David Cain and Lady Shiva as parents, there's a lot of potential. Not to mention her development was closely linked to the League of Assassins, which makes her great fodder for this show.

Batman eventually found her and shaped the assassin for his covert Outsiders unit, but on Arrow, we can get further insight into her dark past (maybe even disguised as the Kasumi alias she used) which haunts her as she attempts to seek redemption. This is a chance for Oliver to relive his own constant attempts to remain in the light and explore Cassandra possibly training with the al Ghuls.

Let us know in the comments which DC characters you'd like to see appear next season on Arrow!