With DC's Arrowverse currently at seven shows and counting, it can be hard to keep track of all of the DC characters who have made an appearance. Arrow set the stage for the expansive universe that fans know today, but unfortunately, many great characters were forgotten along the way.

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Whether they were one-off villains or likable supporting roles, several memorable character arcs were completed almost as soon as they were introduced. Not everyone can get the spinoff treatment like The Flash or Supergirl, but some characters managed to leave a lasting impression on fans with only a single starring turn.

Constantin Drakon (Season 1, Episode 1)

Constantin Drakon was one of the first enemies that Oliver Queen faced in his quest to cross the names off his father's list. A major Green Arrow villain from the comics, Drakon is known for his incredible fighting ability. As one of the first real enemies that Oliver faces in the show, Drakon is Oliver's true introduction into the role of the Arrow. While it would have been nice to see him live longer than one episode, somebody had to be the first casualty of Oliver's war on crime, and Drakon sets the stage for both the gritty tone and the high-stakes action that would define the show.

Dodger (Season 1, Episode 15)

Dodger is different from the shady businessmen or crime bosses that Oliver has dealt mostly with so far. Dodger is a high-class jewel thief with a hefty dose of smarmy charisma and a supposed moral compass. He proves himself to be quite a skilled adversary and could be both a physical and intellectual rival to Team Arrow. It's his Robin Hood mentality that truly sets Dodger apart, however, and he is one of the first to call some of Oliver's own villainous moments into question. Dodger had the charm and the intelligence to be a solid recurring enemy, but unfortunately, he has yet to appear again in the Arrowverse.

Cyrus Vanch (Season 1, Episode 13)

Cyrus Vanch is a great villain for the hilarious simplicity of his evil plot. In order to take out the Arrow, Vanch enacts a plan that would put even the Riddler to shame. He counts how many arrows the Arrow carries with him, and simply hires one extra henchman than that. That's his whole plan. The beauty part is that it almost works too. Oliver is captured and saved by Quentin Lance, forcing them to work together for the first time in the series. It is a significant turning point in the relationship between Oliver and Lance which would remain one of the most important partnerships for the rest of the series, but Vanch is never seen again.

Garfield Lynns (Season 1, Episode 10)

Better known to DC fans as the pyromaniac Firefly, Arrow's Garfield Lynns is a much more human character than many of Oliver's earlier foes. A former fireman who was left to die by his team in a devastating fire, Lynns has returned to seek vengeance on the ones who betrayed him. While his crimes of burning people alive are certainly not justified, Lynns garners much more sympathy than many of the other villains on the show, and makes Oliver realize that some of his targets are really victims themselves. Garfield was once a good man, and his climactic self-immolation offers a poignant end to one of Arrow's most tragic villains. While it's sad that Lynns was killed off, his death serves as an important moment in Oliver's early career.

Mr. Blank (Season 1, Episode 20)

Mr. Blank is a standout among the countless assassins that Oliver Queen has faced off with over the years. The enigmatic killer is never given a name, and little is known about him during the episode. With calm professionalism and a snazzy suit, Mr. Blank is arguably the most realistic and legitimately frightening hired gun of the early seasons.

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His shocking lack of emotion and ruthless attempts to kill a child elevate Mr. Blank past just another hitman into an almost slasher-esque villain. He is easily one of the most unique and intriguing villains of the first season, so it's a shame that his death in the episode's climax means is unlikely to return.

Roy Stewart (Season 7, Episode 19)

General Roy Stewart (Ernie Hudson), is the stepfather to John Diggle and served with Diggle's biological father when he was killed in action. While he is a valuable help to the team, it is Stewart's relationship with John that makes him such a great character. Stewart has allowed John to believe that he is responsible for his father's death for years to protect him from the truth.

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He is willing to accept his stepson's hate permanently to protect John's memory of his father, all while still serving his country. It is a heart-wrenching sacrifice, and makes Stewart's single appearance one of Arrow's best. Stewart has yet to return, but with John possibly becoming a Green Lantern in Arrow's finale, it's possible that Stewart could play a part in his future.

The Dollmaker (Season 2, Episode 3)

The Dollmaker is in competition with Mr. Blank for the creepiest Arrow villain. The Dollmaker is a serial killer who kidnaps women and turns them into macabre dolls to dress up and pose. The Dollmaker himself is not much of a physical threat to the Arrow, but his eerie demeanor makes him a terrifying villain. Like Mr. Blank, Dollmaker veers Arrow into near horror territory, and fully embraces the dark side of Arrow's tone. It's hard not to agree with the Canary when she kills him during a rescue, but the disturbing method in which he kills his victims and his unsettling performance sticks with viewers long after his single episode. As supervillains go, the Dollmaker is a true monster of the week.

Clock King (Season 2, Episode 14)

William Tockman, A.K.A. the Clock King could have and probably should have been a goofy throwaway character, but he surprisingly turns out to be one of the most complex and intelligent villains in Arrow. Tockman is a highly intelligent man who has been diagnosed with a terminal illness, and he robs banks in order to pay for medical treatments. This sympathetic backstory is fleshed out even further when it is revealed that the medical bills that he is stealing for are not even for him, but rather his sister who is also seriously ill. While there are other sympathetic villains in Arrow, none blur the lines quite as well as Clock King. He manages to inspire both sympathy and fear in his one outing. Tockman even returned in an episode of The Flash, but he still only has one Arrow episode to his name.

Chimera (Season 7, Episode 11)

Kevin Meltzer was saved by Oliver Queen towards the beginning of his career, and is dangerously obsessed with vigilantes. He satisfies this obsession by collecting the masks of Star City's superheroes, however he can. Chimera is armed with a high-tech exoskeleton and is an expert fighter, which he demonstrates by holding his own in a fight against multiple members of Team Arrow at once. His surprising combat effectiveness means that he could have been much more of a lasting threat, and his mask collecting habit is one of the most unique MOs of any villain in the show. It's a shame Chimera only got to suit up among the best of Arrow's villains for one episode, but it is possible that he could reappear in another show to capture more masks.

Dick Grayson (Crisis on Infinite Earths Part 1)

Dick Grayson is only on screen for a few seconds, but his brief cameo was all that he needed to make his mark. Actor Burt Ward reprises his role from the classics '60s Batman show in the opening scenes of the crossover which would serve as Arrow's finale. He appears just long enough to spout a hysterical "Holy Crimson Skies of Death!" before his parallel world is destroyed by the Anti-Monitor. In a crossover full of cameos and fan service, this brief appearance is easily a highlight of the entire multi-part event, and is a loving tribute to a famous character. It was a shame Grayson didn't get to suit up with the rest of the heroes in the end.

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