Pokemon 20th Anniversary
That sure is a lovely Pokémon gradientThe Pokémon Company

As the Pokémon franchise celebrates its 20th anniversary, the IBTimes UK team decided to sit down for a calm and measured debate over what we consider to be the five best-designed Pokémon of each generation - from 1996's Pokémon Red, Blue and Yellow all the way through to 2013's Pokémon X and Y. Inevitably, things got heated.

Using a complex algorithm clandestinely obtained from the Poketronics Institute, we meticulously judged the cast of pocket monsters, based on the coolness or cuteness of their design and how much we wanted them to be part of the teams we've assembled and trained over the years.

Gen 1 – Pokémon Red, Blue and Yellow

Pokemon Best Designs Gen 1
(L-R) Charizard, Blastoise, Jigglypuff, Haunter and Vaporeon.The Pokémon Company

Clearly there is an elephant (or should that be a Donphan?) in the room here. Where is Pikachu? Let's be clear: there is no Pokémon more iconic or ubiquitous than the red-cheeked mouse, but we mark the lil' fella down here because of his – let's say big-boned – original design, which was later refined for the TV series. Instead we opted for cutesy pink puffball Jigglypuff.

Classic starter evolutions Charizard and Blastoise have firmly stood the test of time, having been the cover stars of Red and Blue. The fire-breathing dragon and water-cannon turtle-thing beat out their pre-evolutions because the majority of your time with the game was likely spent with them at the top of your team, all the way up to the Elite Four. Sorry Venusaur.

Haunter nips ahead of Gengar as it looks more fearsome and ghostly. Of course we needed to include an 'eevee-lution' on this list as well, to represent one of the most unique family trees in the series. Jolteon and Flareon are great in their own right, but Vaporeon was our pick.

Gen 2 – Pokémon Gold, Silver and Crystal

Pokemon Best Designs Gen 2
(L-R) Cyndaquil, Togepi, Heracross, Houndoom and Lugia.The Pokémon Company

Game Freak's sophomore effort had its fair share of candidates, but of the starters, Cyndaquil was an instant pick. The fiery shrew-like Pokémon was a solid companion throughout Gold and Silver (and later Crystal), able to tear through the first few gyms with ease.

Togepi was beloved by audiences for being Misty's metronome-ing sidekick in the cartoon, but in the games was the catalyst for the series' now-crucial breeding mechanics and Pokémon eggs. Houndoom had a design that defined the freshly introduced dark-type: a mean-looking, mean-battling beast worthy of a place on anyone's best team. Heracross meanwhile, we consider to be one of the best-designed bug-types of any generation.

Lugia, who graced Silver's cover, rounds out our Gen 2 quintet as another easy choice, especially when contrasted with its Gold counterpart Ho-Oh, which looks boring by comparison. Arguably one of the best-designed legendaries of all.

Gen 3 – Ruby, Sapphire and Emerald

Pokemon Best Designs Gen 3
(L-R) Blaziken, Mudkip, Gardevoir, Absol and Rayquaza.The Pokémon Company

Gen 3's new additions include the best set of starters outside the original three. Whether you owned Ruby, Sapphire or Emerald – Blaziken continued the trend of fire-type starters being the most instantly appealing, but this one endured as well, as Blaziken is still well-loved on the competitive scene. Mudkip, meanwhile, gets a place thanks to all of the memes it spawned.

Gardevoir, the elegant psychic-type, would much like Togepi later become a fairy-type and be graced with the accompanying move-set. Back in the day however, it always proved an excellent candidate for the psychic slot on anyone's team.

Next up, Absol, a pure dark-type that could "foretell the coming of natural disasters" according to the Pokédex. A simple, instantly memorable feline design and own of one of the best audible cries in the series.

Finally we chose Rayquaza, the serpentine dragon that seemingly drew a little inspiration from the Dragon Ball series. Blatant influences aside, Rayquaza bucked the bizarre trend of dragons not appearing very dragon-like, and for that reason we were glad we saved our Master Balls for this ancient monster.

Gen 4: Diamond, Pearl and Platinum

Pokemon Best Designs Gen 4
(L-R) Shinx, Gible, Lucario, Shaymin and Arceus.The Pokémon Company

No starters! Shinx was the first on the line-up to really warm our hearts. An adorably designed electric-type kitten, Shinx's wide-eyes had us hook, line and sinker. A long office debate between Garchomp and Gible eventually ended on the side of the miniature shark. Just try and deny that 'dorky' grin. The fact that he eventually becomes an earth-shaking powerhouse just adds to the appeal.

Lucario, a personal favourite of mine, is a lethal steel and fighting dual-type with an iconic aesthetic inspired by the Egyptian god Anubis. Lucario proved an instant hit, as has been proven by appearances in the Smash Bros series and upcoming Pokken Tournament.

While Gen 3 had a lot of legendary Pokémon, Gen 4 really went overboard in this regard, bringing a whopping 13 (or 14 if you count Phione, which is a debate we will not be getting into) mythical beasts to the table. Of those we picked Shaymin, whose violently sweet hedgehog design forced its way onto the list, and the closest thing Pokémon has to an ultimate being – the fearsome Arceus.

Gen 5: Pokémon Black, White and sequels

Pokemon Best Designs Gen 5
(L-R) Snivy, Seismitoad, Zorua, Chandelure and Zekrom.The Pokémon Company

Grabbing the brass ring for grass-type starter Pokémon everywhere in Gen 5 was Snivy, which also has a strong evolution chain. Zorua though, was the equivalent to a standard bearer for this generation. While tricky to obtain, Zorua, the "tricky fox", had bags of charm and a clever illusion ability that disguised it in battle as one of the other Pokémon in your team.

Chandelure is a bit of a controversial choice and split the office. While inanimate objects have not often made good Pokémon, the ornate, gothic-esque chandelier had a winning type combination in fire and ghost and has proved to be a vicious and eerie companion.

Seismitoad and Zekrom occupy the final two spots in a generation that took the very bold step of removing all Pokémon from previous games from its main quest, instead relying entirely on its new cast of creatures which, unfortunately, were not particularly memorable compared to what came before and what was to follow.

Gen 6: Pokémon X and Y

Pokemon Best Designs Gen 6 X Y
(L-R) Greninja, Talonflame, Pangoro, Sylveon and Xerneas.The Pokémon Company

X and Y brought the series into 3D, leaving the sprites of old in the dirt. Picking from the latest collection of pocket monsters was tricky – proving that Game Freak really stuck gold here. No debate was required for Greninja however, who has proved an instant classic (which, like Lucario, led to a bow in the most recent Smash Bros game for Wii U and 3DS).

Representing the, thus far, maligned contingent of bird Pokémon – Talonflame has the appearance of a fearsome raptor and hits like a truck. Sylveon becomes the second 'eevee-lution' to be honoured, as it introduced the world to the new fairy-type. It is a beautiful reimagining of the mythical spirit creatures known as sylphs, and is a firm fan-favourite.

Pangoro showed the world that the docile panda does not play nicely in the world of Pokémon, while Xerneas, the cover star of Pokémon X, closes our countdown by virtue of its dignified but suitably legendary appearance. The best-designed legendary since Gen 3.

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