There are countless franchises that turn into unbelievable phenomena that completely capture pop culture’s attention, and it remains impressive that Pokémon has maintained this success and popularity for several decades. Pokémon is even more beloved than when it made its debut as a quirky video game series. The core mechanics behind Pokémon remain the same, but there have been steady changes that demonstrate the series’ expansion.

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One of the most fascinating aspects behind the growing series is the relationship that exists between humans and Pokémon. Pokémon cover a wide spectrum of cuddly creatures as well as dangerous and destructive beasts, but there are some particular creatures that people have an intense aversion toward.

10 Mewtwo Holds A Deep Grudge Toward Humanity That Doesn’t Know When To Stop

Pokemon PKMN--Ash punches Mewtwo 1400

Each new generation of Pokémon titles introduces a new crop of Legendary Pokémon, but one of the most volatile creatures has been present ever since the original games. Mewtwo is an iconic Pokémon since he’s a creature that’s the result of genetic experimentation. Humanity treats Mewtwo like a guinea pig and so it shouldn’t be surprising when the Pokémon develops resentment toward both humans and Pokémon. Humans have plenty of reasons to fear Mewtwo’s psychic powers, but the fact that he actively targets humans is why this Pokémon is such a big deal.

9 Gengar Properly Demonstrates Why Ghost Pokémon Are Nothing To Joke About

Gengar Pokemon

There are a wide variety of different types of Pokémon, with some of these naturally being more frightening than others. The sheer concept of Ghost-type Pokémon is disturbing and implies that these creatures exist somewhere between life and death. Some very ambitious Ghost Pokémon have debuted over the years, but Gengar is one of the original creations and he’s still a constant terror to Pokémon trainers. Gengar isn’t the biggest Ghost-type Pokémon, but his glee and passion for mischief and terror turn him into a constant threat to humans, even if they don’t believe in ghosts.

8 Alakazam Has Psychic Powers So Intense He Can Wipe A Human’s Mind

Alakazam holding its spoons in the Pokemon anime

Psychic-type Pokémon have been a major danger ever since the first generation of games. They’re far from invincible or without weaknesses, but the premise of telekinetic and ESP-based powers make Pokémon almost seem as strong as superheroes. The Abra evolutionary line is deceptively dangerous because of the latent psychic power in the Pokémon.

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Its final form, Alakazam, is so skilled in this area that it can easily hypnotize humans into being its slaves without them even knowing anything is amiss. Alakazam isn’t a natural predator to humans, but it’s able to gain such control that they need to be prepared.

7 Cofagrigus Is Designed To Deceive & Doom Humans

A herd of Cofagrigus attack in Pokemon

Every new Pokémon game features lots of creative new designs and even the misfires are usually unique enough to prompt discussion. Cofagrigus has a highly unconventional look that speaks to some of the growing pains present in the Unova region of Generation V. Cofagrigus is an intimidating Ghost-type Pokémon that disguises itself as a sarcophagus. Cofagrigus uses this cover to lure in unsuspecting grave robbers, which it then traps within its body. It’s a terrifying concept, and there are countless adventurers who have met their end this way.

6 Hydreigon Is An Aggressive Dragon-Type With Multiple Hungry Heads

Anime Pokemon Cameron's Hydreigon Battle

Dark and Dragon-type Pokémon make up some of the strongest and most frightening of creatures, so any Pokémon that’s a hybrid of them both is likely to be on the more aggressive side. Some Dragon-type Pokémon look tough but are actually docile, yet Hydreigon is a three-headed beast and they all come equipped with a bad temper. Hydreigon’s unusual anatomy seems to make him more temperamental than the usual Pokémon. Hydreigon functions in a way where it believes that any movement is a perceived attack against it and it will retaliate in accordance.

5 Garchomp Is A Dangerous Pokémon With An Intimidating Appearance

Anime Pokemon Garchomp Tournament Fight

Pokémon is full of occasions where it’s not fair to judge a book by its cover, but such principles can sometimes preemptively save lives. Garchomp is a Dragon and Ground-type Pokémon with an extremely aggressive appearance that easily makes him one of the creatures that trainers want to avoid from Generation IV’s Sinnoh region.

RELATED: 10 Most Dangerous Pokémon From Generation 4, Ranked

Garchomp is nightmare fuel and looks like a Pokémon version of a Xenomorph or some sci-fi abomination. To make matters worse, Garchomp is exceptionally fast and can do damage before humans even notice. It’s a Pokémon that people feel extremely vulnerable around.

4 Guzzlord Is A Mysterious Behemoth That Cannot Be Satisfied

Pokemon guzzlord 2

Some of the most unusual and ambitious Pokémon designs come from the recent titles, and there are some big risks taken with the new creatures out of Generation VII’s Alola region. Guzzlord is technically a Dark and Dragon-type Pokémon, but his origins are alien in nature, and it’s an intense anomaly that confuses and frightens the public. Guzzlord looks like an apocalyptic creature that has no patience for humanity or understanding, but the Pokémon also has an unquenchable appetite. This essentially makes Guzzlord a sentient black hole and one of the most dangerous Pokémon to come out of Alola.

3 Gyarados Is Proof That Dangerous Things Can Grow Out Of Small Packages

Anime Pokemon Pikachu Electrocutes Misty's Mega Gyarados

There are now nearly 1000 unique Pokémon designs, but it’s impressive how some of the most memorable creatures are still from the original 151 designs. Gyarados is a popular Pokémon due to how it’s a deadly evolution that grows out of the completely useless Magikarp. Some trainers figure out how to tame Gyarados, but by and large, they’re destructive creatures of the sea that cause unexpected terror while out on open water. Gyarados is frightening in a purely physical sense, but there’s no telling how many sea travelers met their end because of a reckless Gyarados.

2 Yveltal Is Literally Known As The Destruction Pokémon & It’s Not An Exaggeration

Yveltal

Legendary Pokémon typically come across as vessels of destruction, even when they’re actually pacifistic in nature. These prolific Pokémon often deal with the balance of the universe and possess intense powers of life and death. Yveltal originates from the Kalos region in Generation VI, but the Dark and Flying-type Pokémon feels like it should transcend any physical realm. Yveltal has the ability to absorb all of the life that's around it, and it's treated as an immovable process. It's like Yveltal is a living time bomb that can take out all of humanity with it, under the right conditions.

1 Giratina Is A Being Of Pure Darkness That Only Wants To Destroy

Pokemon giratina glowing m18 pokemon movie

Generation IV is a significant turning point for Pokémon because of the Creation Trio of Legendary Pokémon that it introduces. Arceus, Dialga, and Palkia are no slouches and can literally reshape the universe, but Giratina is the black sheep of the family that channels its power into pure malevolence. Giratina rules dominion over the dark Distortion World and needs to be banished away by Arceus because it’s such a threat. Giratina is a direct threat to the entire universe and without a Pokémon like Arceus to keep things in check, the world would likely constantly be afraid of Giratina.

NEXT: 10 Most Dangerous Pokémon From Generation 2, Ranked