Doctor Who has featured many iconic villains and monsters over its almost sixty-year run. The Doctor often goes head-to-head with evil antagonists, sometimes of human nature but often of other-worldly origins.

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One particularly exciting aspect of the latest season is its reintroduction of several fan-favorite villains such as The Weeping Angels and the Sontarans. The season also features some intriguing new threats though such as its namesake - "The Flux" - as well as the deadly Ravagers, Swarm, and Azure who The Doctor fought in her forgotten past.

The Daleks

Daleks in Bad Wolf

The Daleks are one of the best monsters in Doctor Who and certainly the most iconic. In fact, they are the only monster to face off against every single incarnation of The Doctor in the TV show. Unfortunately, due to that iconic status, there can be a tendency to use them simply for fan service or to create renewed buzz which is certainly the case for season 13.

While their inclusion in the season was kept a secret until its broadcast, they are confined to cameo appearances which actually depletes their overall threat as villains. The Daleks are the type of villains that should be saved for huge-scale stories of their own; having them tricked by the Sontarans in the final episode of this season is almost laughable as they have always been shown to be the far more superior adversary of the two.

The Cybermen

Doctor Who Season 13 Cybermen walking towards the camera

Although they do appear in the season, The Cybermen are also confined to cameos. Flux certainly isn't one of the best Cybermen stories in Doctor Who as they barely appear and are slightly undermined when they do. In episode 3, they are easily taken out by solo-fighting Bell which really doesn't ring true with what the audience has seen from them previously.

The Cybermen are given slightly more focus than the Daleks but they are still very much in the background of this season. Due to their large role in the previous season, it's understandable that they're not a huge focus here but it does beg the question as to why they needed to appear at all.

Tecteun

Tecteun's death in Doctor Who

Part of the way through the season, The Doctor meets a mysterious old woman and almost immediately fans began to theorize about who she might be. One of the most common fan theories comes to pass as she is revealed as Tecteun, The Doctor's adoptive mother from back in their "Timeless Child" incarnations. As the character has only briefly featured before, the reveal doesn't hold that much weight but it's still exciting to properly meet her at last.

That being said, one surprising element of the character's reappearance is her villainous nature. As she experimented repeatedly on The Doctor as a child, this is certainly the most satisfying route to go down. While she is cold and calculating, there is very little explanation as to why and it's still unclear why Division is so offended by The Doctor's 'interference' in the universe. Just as it feels Tecteun is about to be explored more, she is seemingly killed by Swarm and any potential for the character dies with her.

The Sontarans

A Sontaran in Doctor Who Season 13

Before the season began, many fans were excited to see the return of the Sontarans who last had their own story all the way back in season 4. The new design of the monsters is certainly more true to their Classic appearances. In addition, they are much more threatening than they've ever been in New Who in the second episode of season 13. The Doctor's confrontation with their leader also serves to show more depth to this incarnation of the protagonist.

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However, with so much to wrap up in the final episode, it is bizarre that the Sontarans are given a second episode at the forefront. Here, they are reduced to cringe-worthy comedy including a strange scene about chocolate bars. Ultimately, the Sontarans are a strong and effective threat in episode two but their appearance later in the season is utterly bizarre.

Passenger

Passenger Standing Beside Swarm and Azure in Doctor Who

Swarm and Azure may be the main villains of the season, but their bodyguard Passenger also plays an important role. The two Ravagers trap people inside the Passenger form including Dan's love interest Diane.

While The Doctor does say the Passenger is a long forbidden form, a lot is left unexplored with this idea, and most of its threat is implied through exposition. The Passenger itself looks like a typical Doctor Who henchman in the best possible way and its presence is foreboding and intimidating. This villain proves instrumental in defeating the final Flux; but, apart from keeping prisoners inside itself, the most menacing aspect of the villain is its appearance.

The Flux

The Flux destroys Outpost Rose

Although the Flux is not a physical being, it is certainly one of the main threats of season 13. As revealed later on, the Flux is created by Division in order to stop what they see as irreparable damage to the universe caused by The Doctor.

Despite the season being subtitled Flux, the true effects of its destruction are seen only fleetingly through scenes with Bell: a character the audience is unfamiliar with. If previous planets or characters from the show were seen in the aftermath of the Flux, the threat could have felt much larger. When the destruction of the Flux is seen on screen though, it is breathtaking and visually stunning and puts the central characters in real jeopardy.

The Grand Serpent

The Grand Serpent in Doctor Who

Despite an unfortunate lack of screen-time or development, The Grand Serpent is still a memorable villain, largely due to the calm and collected yet menacing performance. Excitingly, through this character, the audience is reintroduced to UNIT for the first time in this era. The horned snake that appears from The Grand Serpent to dispatch his victims is a striking piece of imagery that really helps to set the villain apart too.

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Although the audience doesn’t get much time to invest in this character or any of his victims, his attempt to assassinate Kate Stewart is unforgivable. While his infiltration of UNIT is impressive, the character is taken out just as he is coming to the forefront and before he gets the chance to do anything truly evil.

Azure

Azure in Doctor Who season 13, episode 3

One of the major villains of the season is the mysterious Azure, who along who her brother, seems intent on causing chaos and reveling in the destruction of the Flux. While the character is certainly menacing, she is mostly used as Swarm’s right-hand woman and rarely gets the opportunity to be a character in her own right.

As a character from The Doctor’s past, there is a lot that could have been explored with Azure so it's disappointing she wasn't used more. Azure’s evil nature is fully showcased when she is seen taunting Diane and when she disintegrates the triangle priest without a second thought. Despite falling into the background a little in the second half, Azure is still one of the most captivating villains from season 13.

The Weeping Angels

Doctor Who Season 13 Weeping Angels

Since their debut back in season 3, The Weeping Angels have become iconic and have featured in some of the scariest episodes of Doctor Who. Finally seeing this villain back in the focus is brilliant and for the most part they're just as menacing as ever.

The fourth episode of Flux focuses heavily on The Weeping Angels and it's certainly the most thrilling and action-packed episode of the season. Their concealing of The Doctor in stone and the gleeful killing of Peggy's guardians shows just how meniachal these villains can be. The Weeping Angels are a highlight in season 13 and are just as threatening and terrifying as they've ever been.

Swarm

Swarm in Doctor Who Flux

The main villain of Flux, Swarm is an exciting new addition to the show’s mythos. At the start of the season, he escapes his prison and it soon becomes clear that he has a history with The Doctor that she is unfamiliar with.

Where the previous two seasons have struggled to create memorable new villains, Swarm is a threatening presence that is bound to have younger fans hiding behind the sofa. The actor’s performance is electric and the brutal way in which he uses his disintegrating abilities is terrifying. Much like with Azure, he is defeated far too easily but still seems to steal any scene he’s in. Swarm is undoubtedly one of the best characters from Doctor Who: Flux and many of the best lines and scenes from the season involve him and his confrontations with other characters.

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