For a series that’s generally pretty light-hearted, Fairy Tail has introduced its share of pretty scary villains: dragons, demons, demented immortals. It makes sense though: in a world where magic is everywhere and can be expressed in a nearly infinite amount of ways, it’s only logical that someone would come up with a bunch of twisted ways to take advantage of their powers.

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With the anime coming to an end after ten years, there’s no better time to do some reflection. So for this list, we’re looking at some of the most dangerous villains in Hiro Mashima’s epic shonen fantasy series.

10 GAJEEL

Iron Shadow Dragon Mode Gajeel Fairy Tail

Though now we know of him as one of the most loyal members of the guild, willing to fight to support them until the end, that also hasn’t always been the case. When Gajeel was first introduced he was a member of Phantom Lord’s elite fighting force, the Element 4.

He was the first person to start the guild war between Fairy Tail and Phantom Lord, and seemed to have no problem roughing up the members of Shadow Gear to prove his guild’s superiority. It was only after being pummeled by Natsu and accepted into Fairy Tail by Makarov that he began to change.

9 LAXUS DREYAR

Fairy Tail has the worst luck with its members. Gajeel joined the team after first attacking them, at least. Laxus was already a member of the guild, and worse, he was the grandson of the current Guild Master, Makarov. Nonetheless, Laxus found himself frustrated by the guild’s lackadaisical nature of handling things and focus on family.

He had several members of the group turned to stone while attacking the remainder, attempting to have them all kicked out of the guild. In the end, it took both Natsu and Gajeel to take him down, and even then only because Laxus inadvertently gave Natsu a massive power boss via his lightning attacks.

8 ERZA KNIGHTWALKER

Erza has always been one of the mainstays of Fairy Tail, and one of their most powerful wizards. She’s been in line to be considered one of the Ten Wizard Saints of Fiore, and she’s completed countless difficult S-Class missions.

So when the team visited the alternate world Edolas and meet otherworld versions of themselves, learning Erza’s alternate version was a villain was something that caused a bit of concern. Unsurprisingly, Knightwalker was able to battle the real Erza until their fight reached a standstill. Powerful and bloodthirsty, the only weakness this version has is she’s unable to use magic like the original.

7 ULTEAR

ultear milkovich fairy tail

Part of the reason Ultear ever became a villain in the first place was that she had far too much magic for her own good. Her latent power left her ill as an infant, and her mother Ur’s attempt to help her resulted in Ultear being kidnapped by the organization, experimented on, and having her powers increased.

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By the time we meet her in Fairy Tail, she’s an adult woman who’s joined Grimoire Heart and become one of their most powerful members. Her Arc of Time powers alone make her a high-level threat, but she also gained her mother’s Ice Make abilities, meaning she’s a dual threat that Gray was lucky to not get killed by.

6 HADES

Hades speaking while wearing an eyepatch in Fairy Tail

Even though Fairy Tail prides itself on loyalty, they somehow have a ton of traitors. Like the second Guild Master of Fairy Tail, Precht. Driven evil by his attempts to bring back Mavis, Precht would go on to form the guild Grimoire Heart. Thanks to his years of study however, Hades grew to become far more than the mage we were introduced to in Fairy Tail Zero.

He’s able to absorb other people’s magic, abuse bullet magic which fires fast enough to resemble actual bullets, and use magic shockwaves capable of wrecking parts of an island. It’s no wonder if took the combined forces of Natsu, Gray, Wendy, Lucy, Laxus, and Erza to stand a chance at defeating him.

5 MARD GEER

Natsu and Gray Vs. Mard Geer

The head member of the curse demons from the Books of Zeref, Mard Geer seemed unstoppable when he was introduced. His Memento Mori ability alone is referred to as the ultimate curse, one which erases the person hit by it, turning them into absolute nothingness.

But he also has his Etherious form, a monstrous Bat-like form he was able to use to fight Natsu, Sting, and Rogue to a standstill. It’s only when Natsu finds his way into Dragon Force while Gray uses his Ice Devil Slayer abilities that any human is able to defeat him.

4 AUGUST

The Wizard King August is the son of Zeref and Mavis, so it’s no surprise he’s got some incredible abilities. Much like Irene, there are very few limits placed on what he’s capable of doing. His primary power is fairly simple: he can copy any other person’s version of magic, instantly mastering it and even proving immune to the magic.

He can do all of this without ever having to have battled his opponent as well. He can just see the magic to do all of this. August’s only weakness is he can’t copy the powers of magicians who use special items, as he must possess those items to do so.

3 IRENE BELSERION

Irene Belserion making a coy, conniving grin in the Fairy Tail anime

The Mother of All Dragons...and Erza Scarlet. It’s no wonder Irene is considered one of the most powerful members of the Spriggan 12, an organization where nearly every member is more powerful than the vaunted Ten Wizard Saints of Fiore. Irene was the woman responsible for developing Dragon Slayer magic to begin with, and its power gradually turned her into a Dragon as well.

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But that’s not where the extent of her magic stops. Irene is also capable of casting enchantment spells so powerful she can give personalities and magical abilities to inanimate objects. She has seemingly limitless magical power and takes pleasure in finding new ways to use it to decimate foes.

2 ZEREF

Zeref Getting Angry And Releasing His Black Magic

Zeref is one of the most dangerous mages in all of Fairy Tail, hero or villain. His legend alone as an immortal wizard with almost infinite power inspired countless Dark Guilds worshipping him and trying their best to get him to awaken once more. Zeref isn’t only a genius at magic, he’s also had centuries to research, refine, and practice his abilities.

Even more ridiculous is that his powers literally channel decay itself, meaning it can kill or seriously injure nearly anything it touches.  He can't even entirely control his powers, as anything he cares about will be destroyed if it's near him.

1 ACNOLOGIA

The entire series built up to this guy, and rightfully so. From the moment he was first mentioned we understood him to be more powerful than anyone else the team had ever faced. Gildarts’ introduction was with him mentioning he’d tried to fight Acnologia and walked away with fewer bodyparts.

He attacked the biggest members of Fairy Tail on Tenrou Island and it was only the timely intervention of Mavis that stopped them from dying. If the Dragons were the biggest threats humans ever faced, then as the King of Dragons it makes sense that Acnologia would be the most dangerous.

NEXT: Fairy Tail: 10 Things Only True Fans Know About Gajeel Redfox