Believe it or not, the Ezra Miller-led solo film for The Flash starts filming in 2021 under director Andy Muschietti, three full years after it was originally supposed to hit theaters. The Flash took a long time for numerous reasons and is now as close to happening as it's ever been. It seems Barry Allen, Iris West and potentially Henry Allen will appear in the film, but which villain will The Flash face off against?

The Flash has one of the best, most interesting group of adversaries in all of comics. There are a handful of notable villains that could be used as the main bad guy in The Flash without falling short of the usual hero/villain showdown. However, there are a few key villains from the pages of DC history that would make perfect villains for the speedster in live-action. Let's get started.

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Eobard Thawne aka The Reverse Flash

One of the downfalls of The Flash TV show is the incessant need to include a speedster villain for Barry practically every season. However, there is one speedster worthy of being Allen's foil in the movie adaptation: The Reverse Flash. Eobard Thawne is essentially an evil version of The Flash with similar powers and abilities.

In the comics, Thawne goes back in time to before he even met Barry to fill his life with tragedy. The two are rivals in the future and the Reverse Flash intends to make Allen's life miserable before he even gains powers from the Speedforce. Thawne murders Barry's mom and frames his dad for the murder - a plotline that has already been set up in Justice League, as Allen's dad is seen serving time for his mom's murder in prison. Throwing Thawne into the mix would make the story personal, allow for some time travel zaniness and pure spectacle while adding to the events of Justice League. If they really want to expand The Flash's universe, the Reverse Flash would be a perfect inclusion.

Gorilla Grodd

Gorilla Grodd is a super-intelligent gorilla from Gorilla City who's got telepathic powers and enhanced strength thanks to a chance encounter with an alien spacecraft. The Legion of Doom member has long been a thorn in The Flash's side as his escapades from Gorilla City to Central City have often resulted in devastation.

While having a gorilla villain could be played up for comedic value, Grodd's quest for respect and domination would make quite an interesting arc. Plus, it would be cool to see Grodd in live-action with a full budget and team behind him. He seems more like a sequel villain, but Grodd deserves to show up at some point.

The Rogues

Weather Wizard creates a lightening tornado

The Rogues would make an incredible addition to The Flash. The group has had many variations over the years, but is generally led by the devious Captain Cold and includes the likes of Mirror Master, Heat Wave, the Weather Wizard, Trickster, Pied Piper, Top, and Captain Boomerang.

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Taking the core members of the group including Cold, Mirror Master, Weather Wizard and Heat Wave would give Allen a group of adversaries who could collectively take him down. Each Rogue possesses a certain skill that in combination would work terrifically against The Flash. Cold can slow him down with his freeze gun, Heat Wave could warm him up, Mirror Master could pop up in mirrors or drag Barry to the Mirror World, and Weather Wizard could set up some jawdropping set pieces involving terrible weather like a tornado or tsunami.

For a character as fast as The Flash, the more villains he faces, the more trouble it causes him. Against just one of The Rogues, Allen should come out on top. Against all of them? It's not so easy. There's strength in numbers.

Flash movie villains The Rogues

It makes sense to adapt The Rogues because it would expand The Flash's universe while taking the story where it needs to go. Like the Reverse Flash, members of the Rogues could be connected to Allen's father in prison. Regardless, it would be neat to see The Rogues get their due on the big screen. Sometimes more is better, and that's exactly the case with this supervillain group.

It's exciting The Flash has so many different avenues to choose from when it comes to picking a villain. Thankfully, unlike some other DC heroes, Allen has a great crop to choose from. There's serious potential for The Flash when it comes to picking a bad guy - which is why it's great to see the movie live on. Plus, whoever isn't showcased in the solo film can be filed away for a later installment.

Unlike a portion of superhero movies that have trouble finding balance with a villain, one of The Flash's greatest strengths is its expansive roster. It will be fascinating to see which direction the film goes with them.

NEXT: The Flash's New Mission: Become DC's SEXIEST Man Alive