I’m Luke Summerhayes, and I love Deino.
Apart from in rare mutations, multiple heads are not common on real life animals. Nonetheless, perhaps as a result of someone seeing a shocking lizard or snake, multi-headed dragons are very common in mythology. The Hydra in ancient Greek myth serves as a useful metaphor for real-life evils and struggles, thanks to the way removing one head sees two grow in its place. The eight-headed Orochi of Japanese myth is one of the primary villains of that country’s folklore.
And of course, the king of the monsters himself, Godzilla, has a three-headed arch nemesis. King Ghidora first appeared ten years after the original Godzilla movie, and has served as the big G’s deadliest enemy in most incarnations since. With both multiple heads and lightning powers, King Ghidora has a mythic, totemic quality and is almost as iconic as Godzilla itself.
Deino is a dark and dragon type Pokemon with only one head and, thanks to what seems like an emo-style fringe over the top half of its face, seemingly zero eyes.
White
They cannot see, so they tackle and bite to learn about their surroundings. Their bodies are covered in wounds.
Black 2
Lacking sight, it's unaware of its surroundings, so it bumps into things and eats anything that moves.
White 2

The Japanese name for this Pokémon is Monozu, combining mono, or one, with zu, the Japanese for head. I bet you can’t guess what the evolutions are called in Japanese. For once, the English name is more interesting. Deino combines ein, the German for one, with Dino, short for dinosaur. In this particular spelling, it is similar to the Greek word for terrible, often used in the names of dinosaurs and other prehistoric creatures, like Deinosuchus. On top of all that, this is also the name of one of the Grey sisters of Greek myth, a trio of sisters whom Perseus encounters in his quest to defeat Medusa. If we count the snakes of her hair, Medusa is another many-headed monster! These sisters of hers shared one eye. While one of them could see, the other two were, like this Pokémon, blind.
Scarlet
It can’t see, so its first approach to examining things is to bite them. You will be covered in wounds until a Deino warms up to you.

It is worth putting in the time to get a Deino to warm up with you, as at level 50 it evolves into Zweillous.
Zweillous is a little bigger and bulkier than Deino. A pair of tracked red stripes on its tummy betray that, earlier in development, this Pokémon was more militaristic in design, taking inspiration from a tank just as octillery did in the second generation. Even without this element, the Pokémon is still an aggressive one – primarily to itself.
Scarlet
The two heads do not get along at all. If you don’t give each head the same amount of attention, they’ll begin fighting out of jealousy.

Most Pokédex entries talk about these two aggressive heads, while also talking about the subsequent voracious appetite. Zweillous is the concept of “an extra mouth to feed” made literal!
White
Since their two heads do not get along and compete with each other for food, they always eat too much.

Shield
Their two heads will fight each other over a single piece of food. Zweilous are covered in scars even without battling others.

The name Zweillous combines zwei, the German for two, with either jealous or zealous, either of which could apply to its competitive heads and their aggressive consumption. The Japanese name, inevitably, is Dihead, because of the two heads.
Violet
The two heads have different likes and dislikes. Because the heads fight with each other, Zweilous gets stronger without needing to rely on others.
Ironically, in actual game terms, Zweilous requires a lot of battling to get stronger. Pokémon’s fifth generation is infamous for evolutions with high level requirements, and so are so-called Pseudo-Legendary Pokémon. Zweilous lives up to both by waiting until level 64 before it evolves into Hydregion.
Hydregion is a bigger, three-headed dragon, hovering with a more traditional dragon-like body type than the dinosaur-like previous forms. Close observation will reveal that Hydregion only has two legs to its predecessors’ four. In fact, rather than expanding from two heads to three, Hydregion has downsized from two heads to one, its forelegs become head-like arms.
White
The heads on their arms do not have brains. They use all three heads to consume and destroy everything.

Considering the jealousy and infighting of Zweillous, it could be that one head has finally slain the other. I prefer to think they settled their differences and combined, making one smarter super-head.
Scarlet
Only the central head has a brain. It is very intelligent, but it thinks only of destruction.
JAY

We know about the scrapped tank version of this monster thanks to an interview with long-time Pokémon artist Ken Sugimori. In the same conversation, he said that the renewed design was inspired by Yamata no Orochi.
Players of Okami will remember this eight-headed dragon as a recurring boss. This boss fight is based on the most famous story of Orochi, which sees the God Susanoo put it to sleep with a special sake and cut off its heads. This tale of a thunder god slaying a dragon or serpent is one of the so-called monomyths, appearing in different forms in cultures all over the world, presumably coming from a common ancestor. Orochi or references to it appear throughout Japanese folklore and pop culture, being one of the primary villains of Japanese mythology
Black
This brutal Pokémon travels the skies on its six wings. Anything that moves seems like a foe to it, triggering its attack.
Sword
There are a slew of stories about villages that were destroyed by Hydreigon. It bites anything that moves.
Shield
The three heads take turns sinking their teeth into the opponent. Their attacks won't slow until their target goes down.
As well as this animal brutality, Hydregion also imitates the villainous Orochi by being the signature Pokémon of Ghetsis, the arch villain of the Unova games. Ghetsis is one of the least redeemable villains in Pokémon lore, so it makes sense he would use the Pokémon equivalent of the arch nemesis of both Godzilla and Japanese folklore at large.
Ghetsis’ Hydregion is infamous for having the move Frustration, which is stronger the less happy a Pokémon is, at maximum power. It’s clear Ghetsis did not treat this dragon well, and as we all know, no Pokémon is inherently good or evil.
Violet
It's said that Hydreigon grew ferocious because people in times long past loathed it, considering it to be evil incarnate and attacking it relentlessly.

Ghetsis did get one thing right, though; using Hydreigon makes a lot of sense. With a nice spread of moves and chunky attack stats both physical and special, it can do a lot of damage. On top of that, Hydreigon’s dark type rather than flying, as is common with other powerful dragons, lets it avoid the common stealth rock damage, all while its levitate ability lets it ignore earthquake. The later introduction of fairy types wasn’t the best news for Hydreigon, but it’s type coverage meant it did do very well among Dynamax and Terastelisation.
The name Hydreigon combines hydra and dragon while incorporating the word for three. Orochi famously has eight heads, and Sugimori claims the strange, ribbon-like wings are supposed to suggest the other heads when Hydreigon is viewed in silhouette. The Japanese name is Sanzandora, with san being the Japanese for three, Zan coming from the Japanese for brutal or cruel, and Dora coming from wither the Japanese reading of Hydra or Godzilla’s own Ghidora. After all, this Pokémon evolves at level 64 and King Ghidora first appeared in a 1964 film.

Multi headed monsters can be fearsome or wacky. Hydreigon and family manage to dip their feet into both along the way, before becoming one of the most fearsome and well-loved monsters of its generation.
Original music for Luke Loves Pokémon is by Jonathan Cromie. Artwork is by Katie Groves. Funding is provided by listeners at Patreon.com/PodcastioPodcastius. For just a dollar a month, supporters can listen to episodes a week early and also help cover hosting and fees, making it possible for me to keep making episodes every week.
I love hearing from listeners! Get in touch about upcoming Pokémon on twitter or facebook at LukeLovesPKMN. Drop a comment if you’re watching the video, or a review on apple podcasts or spotify. Coming up are Larvesta and Cobalion, so please get in touch about those or any other monsters.
Even if you don’t feel like doing any of that, thank you so much just for listening.
I love Deino. And remember, I love you too.