With Harley Quinn's second season just around the corner, it's the perfect time to reflect on what we've seen from the series so far. The adult-orientated animated show was a major success for the DC Universe streaming service, garnering praise from fans and critics alike. It features an all-star voice cast and a roster of heroes and villains that would put most comic-book adaptations to shame. However, although great on their own merits, some characters outshined others in significant ways.

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CBR is here to rank the ten best characters from the DC Universe show in definitive order. While we love them all, not everyone can make the list.

10 SY BORGMAN

Sy Borgman from the Harley Quinn animated series

The former spy begins as an unlikeable landlord that impedes the main team in their quest of villainy, but Sy Borgman eventually becomes a worthy ally of Harley and co. His involvement in the show expands further along the freshman season, with the final episodes featuring some of his finest moments assisting our favorite villains.

Seinfeld veteran Jason Alexander lends his voice to bring the relatively unknown character to life in an entertaining fashion. Although one can make a case that Borgman isn't as important as the rest of the characters on this list, his presence certainly adds a specific perspective to the show in ways that others don't.

9 KING SHARK

King Shark in the Harley Quinn animated series

Similar to Clayface, King Shark is flipped on his head as the character receives a light-hearted, intelligent version of the DC villain. Instead of being barely able to read in the comics, Shark is a big-time nerd that assists the team with his technological knowledge. It's a switch-up that works extremely well while still doing the character justice.

The one complaint is that he doesn't have much to do for most of the season. Perhaps the new episodes arriving in April will rectify this situation.

8 KITE MAN

Hell yeah. Made recently popular in Tom King's Batman run, Kite Man is one of the hero's most ridiculous villains, which makes him perfect for Harley Quinn. Although King portrays him as a tragic character, the animated series takes a much more simplistic route. Hilariously voiced by Matt Oberg, Kite Man becomes a laugh-out-loud part of the show that strays the line between sincerity and idiocy.

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He's the type of guy that was definitely in a stereotypical frat house before becoming a full-fledged, sort-of useless, villain. Despite that, his relationship with Poison Ivy is certainly a genuinely endearing highlight of the series.

7 CLAYFACE

Despite his grisly appearance, Clayface turns out to be one of the most likable characters of the series. He’s the soft spot of the main crew, always trying to lend his acting abilities in every situation. He’s not the straight-up villain he’s normally portrayed as in the comics, but switch-up works marvelously on the series.

His shape-shifting abilities create some of the funniest moments between the team, on and off the field. Clayface is just one of several DC characters that are successfully redefined for adult audiences in Harley Quinn.

6 COMMISSIONER GORDON

Commissioner Gordon in Harley Quinn TV Show

Commissioner Gordon, voiced by Law & Order: SVU veteran Christopher Meloni, is an absolute revelation in Harley Quinn and serves as a hysterical interpretation of Batman's best friend. Unlike the tough-as-nails cop he is in the comics, Gordon is in a midlife crisis on the brink of losing his wife and his sanity. Although played for laughs at times, it's actually a fairly realistic portrayal of a man who has confronted the worst of Gotham for decades, day in day out.

His one-sided relationship with Batman is also explored explicitly in an episode, which helped flesh out both characters in the villain-orientated show. Despite the differences to the source material, Commissioner Gordon is a fully-realized character that deserves a spot on this list.

5 JOKER

The Joker from Harley Quinn smiling in an office

Although the Joker isn't one of the leads, you can't deny the series does an exceptional job with the iconic Batman villain. Voiced by Alan Tudyk, the character remains as diabolical as ever as the abusive and clinging ex of one Harley Quinn. The writers wisely do not shy away from his destructive role in the protagonist's life, no matter how entertaining he can be.

On the surface level, he's just a great version that rivals the many others that have lent their voices to the Clown Prince of Crime. From the voice to the character design, there's no doubt this Joker will stand the test of time.

4 DOCTOR PSYCHO

Tony Hale lends his voice talents to Doctor Psycho, a crude telepathic metahuman that joins Harley Quinn's crew after a problematic run-in with nemesis Wonder Woman. It's an absolutely hilarious performance that plays on the real-life situations of celebrities being "canceled" in a thoughtful way. He's by far the worst person of the group, however, he slowly but surely grows close with his new family and tries to be a "better" person by the end.

Although most of the characters have their own comedic value, Doctor Psycho never fails to have you in gut-wrenching laughter.

3 BANE

He may only appear in brief instances, but there is no denying Bane steals the show every single time. Clearly inspired by Tom Hardy's iteration of the character, Harley Quinn turns him into an awkward, sympathetic villain that just doesn't quite fit in with the Legion of Doom. He's consistently ridiculed for his outrageous ideas, an outcast within the world of villains.

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Within a mountain of comedic personalities, it’s significant how Bane always manages to outshine his fellow criminals.

2 POISON IVY

Poison Ivy’s role in the animated series is arguably as important as Harley’s, and neither would work as well without each other. Ivy serves as the perfect companion to Harley but don’t get it twisted, she has a compelling story herself. While Ivy helps her friend recover from a toxic relationship, she struggles to find her place in the villain industry.

Her relationship with Kite Man is both endearing and hysterical as the first season chooses to keep Harley and Ivy simply BFFs. It’s hard to imagine the show would be anywhere near as great as it is without her.

1 HARLEY QUINN

As the lead of the show, it’s no surprise Harley Quinn is at the top of this list. However, one cannot overstate how well the series handles the fan-favorite character and takes her to new heights. On a narrative level, their approach to Harley is engaging and thoughtful in almost every way. Kaley Cuoco firmly puts her own stamp on the villain, surely serving as a benchmark for future adaptations.

Despite being in a sea of other popular DC characters, Harley ends up being the one you come back for every week. She works perfectly alongside a strong supporting cast, but the show hinges on her development every step of the way.

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