When Clark Kent entered high school in 2001, he was still developing his many superpowers. When the series began, Clark possessed only a fraction of the strength, speed, and durability he would one day achieve while sporting a red cape. Over Smallville's 10 seasons, Clark would become more powerful and gain more powers like heat vision and super hearing.

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He would certainly need more powers to combat stronger foes. After Clark and his friends graduated from high school, Smallville began introducing more characters and concepts from classic DC Comics lore. Superman villains like General Zod, Brainiac, and Doomsday entered the series, and suddenly, Clark faced creatures and fellow Kryptonians that matched or even exceeded his own strength.

10 Victor Stone As Cyborg Is Strong & Versatile

Victor Stone becomes Cyborg

While he never reaches the strength or durability of a Kryptonian, Victor Stone, thanks to his endoskeleton and cybernetic enhancements, is one of the strongest human characters in the series. Victor was a star athlete and wide receiver for Metropolis High before suffering near-fatal injuries in a car accident that killed his family.

Victor was resurrected after many technological experiments. Now, he possesses superhuman strength and speed and doesn't tire as easily as other humans. He also has the power of technopathy, allowing him to communicate with and manipulate technology.

9 Aldar, A Being From The Phantom Zone Capable Of Killing Clark

The Phantom Zone wraith Aldar challenges Clark

During the season five finale, General Zod, inhabiting Lex's body, trapped Clark in the Phantom Zone. The Zone is a plane of existence that acts as a prison for some of the most dangerous criminals in the universe. Clark escaped thanks to the Crystal of El but unknowingly freed several "phantoms" with him.

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Among the escaped was a hulking being known as Aldar. Aldar finds Clark and easily overpowers him, coming within seconds of ending his life. Fortunately, a shadowed individual comes to Clark's aid. Even though Clark was only 19 years old, the fact that Aldar outmatched a Kryptonian was impressive and scary.

8 J'onn J'onzz Saves Clark's Life Many Times

martian-manhunter-smallville-john-jones

Martian Manhunter is one of the most powerful heroes in DC Comics. His Smallville counterpart is similarly very powerful, though not quite as powerful as his comic book counterpart. J'onn J'onzz is a Martian and the sole survivor of his kind. He came to Earth to aid Clark in his journey of becoming the universe's greatest hero.

He helped Clark defeat Aldar and the Phantom Zone wraiths and even flew Bizarro to space. At the height of his power, J'onn is nearly unstoppable, possessing super-strength, invisibility, intangibility, and much more. Unfortunately, he's quite nerfed in the show and loses his powers for much of his screen time.

7 Bizarro Is As Strong As Clark But Has Many Weaknesses

Bizarro reveals his true self to Clark

Smallville's Bizarro is very different from the Bizarro seen in the comics. This Bizarro wasn't created in a LexCorp laboratory, and he didn't come from an alternate universe. This Bizarro is actually a Phantom Zone wraith, capable of replicating the body and powers of another.

This wraith mimics Clark, creating a "bizarre" version of him. Bizarro is extremely deadly, possessing all of Clark's powers as well as the ability to fly. Instead of being weakened by Kryptonite, Bizarro absorbed it to gain more power. Instead of absorbing yellow sunlight, Bizarro's body rejected it like a vampire.

6 Kara Zor-El Develops Powers Faster Than Her Cousin

Kara is Supergirl in Smallville

Kara is Clark's cousin from Krypton. Her spaceship landed on Earth along with his, but she was trapped in stasis, awoken when Clark was an adult. Kara is headstrong and stubborn which possibly helps her develop her Kryptonian powers much faster than Clark, learning to fly within months of waking up.

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Her quick accumulation of power can be chalked up to the fact that she is much more prepared and accepting of her Kryptonian heritage. Clark is on a journey, but Kara is on a mission. Kara was already an adult when Krypton neared its end. When her father sent her to Earth, she was instructed to watch over her cousin. Clark spent most of his childhood unaware that he was an alien.

5 General Zod Uses Lex Luthor As A Vessel

Zod escapes the Phantom Zone

General Zod has appeared many times throughout Smallville in various forms. Brainiac first attempted to resurrect Zod using Lex Luthor as a host body. Lex was given all the powers of a fully developed Kryptonian before Zod inhabited his body. Clark would banish Zod's mind to the Phantom Zone using the Crystal of El.

Later, younger versions of Zod and his Kryptonian lieutenants were resurrected on Earth. Though this young Zod originally possessed no powers thanks to Blue Kryptonite radiation, he would obtain them and become just as powerful as Clark in season nine. This Zod was defeated after Clark used the Book of Rao to transport him to another world. No matter what form he takes, Zod just can't catch a break.

4 Doomsday Is A Nearly Unbeatable Killing Machine

Doomsday achieves his true form

Doomsday is one of the most powerful and terrifying creatures in DC Comics history for one reason: he killed the Man of Steel. Killing Superman is no easy feat, but it's a feat that made Doomsday infamous. Fans were more than excited when Doomsday was announced to appear in season eight. Throughout the season, Doomsday develops in the host body of Davis Bloome until he achieves his true, monstrous form.

Clark is unable to defeat him. Instead, Clark lures Doomsday into a trap at the Earth's core. Doomsday appears to be stronger than Clark in every way and cannot be defeated the same way twice. He's weakened by Kryptonite, but quickly develops an immunity to it.

3 Clark Luthor Reaches His Full Potential Through Violence & Control

Clark Luthor enters the Fortress of Solitude

What if baby Kal-El wasn't found by the Kents? What if he was discovered by Lionel Luthor? How much of Superman's morality and responsibility was taught to him by Jonathan and Martha? Season 10 looked to answer these questions when it introduced viewers to Clark Luthor, an evil version of Clark Kent from Earth-2.

This Clark was raised to rule the world with an iron fist. It's alluded to that he killed his adoptive brother, Lex, in order to win Lionel's approval. Clark Luthor is just as powerful as Earth-1 Clark, if not more so. When the two Clarks first meet, Clark Luthor can fly, an indicator of a Kryptonian who's achieved their full potential.

2 Brainiac Is One Of The Smartest, Deadliest Beings In The Universe

Brainiac from Smallville

Brainiac, brilliantly played by James Marsters, was one of the best villains of the series. He first appeared at the end of the season five premiere and disguised himself as Clark's college professor and ally. He quickly revealed himself as Brainiac, an advanced AI created on Krypton with the mission of resurrecting General Zod.

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Brainiac seemingly possesses all the powers of a fully developed Kryptonian. As if that wasn't enough power, he can also shapeshift, hack technology and minds, and contains almost all knowledge of the known universe. Brainiac was a villain who just couldn't stay down, returning many times throughout the latter half of the series in various forms.

1 Clark Reaches His Full Potential In The Series Finale

Clark stands on the Kent Farm in Smallville

Like any other Kryptonian, Clark achieves his full biological potential when exposed to the Earth's yellow sun. In Smallville's first season, Clark is shot in the back, but the bullets only leave bruises. By the second season, Clark can intercept bullets while sustaining no damage, proving that the longer he remains under the yellow sun, the stronger he becomes.

Over Smallville's 10 seasons, Clark develops classic superpowers used by his comic book counterpart. In the series finale, Clark finally achieves the power of flight, fulfilling Jor-El's vision, and becoming Superman to save Earth from the invading Apokolips. Clark's unknown limitations are teased in episodes like "Hereafter" which imply that Clark/Superman has no limit to his power.