When you are playing Pokémon with your friends, there are usually no rules or stipulations when choosing a team. In the old days, this usually meant a battle between people who were using the same team that they completed the single player mode with, against a player with a team full of legendaries. What most players did not realise at the time was that not all Pokémon are created equally. The stats that make up a Pokémon are based on numerous factors. If you want to create a truly powerful Pokémon, then you best be prepared to spend a lot of tedious time running around the Day Care Centre.

Some players choose Pokémon for their designs. This is certainly one of the reasons that Mimikyu from Pokémon Sun & Moon has made its way into so many teams. The strength and ability of a Pokémon has no bearings on its appearance. It is for this reason that some players might be ignoring powerful Pokémon, due to a dislike of their design. We are here today to shine a spotlight on the Pokémon that you should take a second look at. From the happy egg who will murder you in your sleep to the cheap squirrel who took the gold medal.

Here are 15 Pokémon You Never Realized Were Ridiculously Overpowered.

15. Chansey

Chansey holds its hands together in Pokemon

Chansey looks like - A pink egg on ecstasy.

Don't let that smiling face fool you. Chansey has been the terror of the Pokémon competitive scene since Red & Blue.

With its very high HP and special defence stats, Chansey is a hard Pokémon to defeat in battle. A popular strategy in the Generation 1 days was to use moves like Minimize and Double Team to boost Chansey's evasion. This meant that you would struggle to even hit Chansey in the first place and would barely even damage it when you did. Chansey also had exclusive access to Soft-Boiled, a 50% healing move. While the enemy Pokémon struggled to land a blow, Chansey could just wail on them with Thunderbolts and Ice Beams.

Chansey's reign of terror continues into the modern era, with the addition of an item called Eviolite. In Pokémon Gold & Silver, Chansey gained an evolution known as Blissey. Pokémon Black & White introduced Eviolite, an item that boosts the defence and special defence of a Pokémon who can still evolve. This turns Chansey into a defensive wall that many other Pokémon will struggle to tear down.

14. Amoonguss

Amoonguss looking angry in the Pokémon anime

Amoonguss looks like - A Pokéball themed Cenobite from Hellraiser. 

Amoonguss is a Grass/Poison-type Pokémon that was introduced in Black & White. From the outset, it's obvious that Amoonguss had little care put into its design. The people at Game Freak just drew a Pokéball on one of the mushroom monsters from Dark Souls and called it a day. While not impressive to look at, Amoonguss has a few tricks up its sleeve that turns it a powerhouse on the battlefield.

The thing that makes Amoonguss so great is his move selection. He is one of a handful of Pokémon that can use Spore, a move that will inflict the Sleep status with 100% accuracy. Alongside his range of powerful status effect and Poison-type attacks, Amoonguss can also have the Regenerator ability. This allows him to heal a third of his health whilst switching out. This makes him great for throwing status effects on the enemy, whilst giving him the ability to survive a counterattack.

13. Clefable

Clefable Pokemon

Clefable looks like - Gengar before his Goth phase.

The Cleffa/Clefairy/Clefable line is not the most visually interesting group of Pokémon. It might come as a surprise to learn that Clefairy was once considered for the role of series mascot. A rogue Clefairy is actually one of the main characters in Pokémon Pocket Monstersthe oldest running Pokémon manga series. This line never saw much play in the competitive scene... at least before the sixth generation of games.

When Fairy-type was introduced in Pokémon X & Y, Clefable suddenly became a legitimate threat in battle. Clefable changed from Normal to Fairy-type, which took away the crippling type-weaknesses that were holding it back in the past. Clefable gained a few powerful Fairy moves (like Moonblast), which made it an effective counter to Dragon-type Pokémon.

The Clefairy line has one of the best built-in abilities in the game - Magic Guard. This ability protects the Pokémon from indirect damage. This means that Clefable cannot be damaged by weather or entry hazards (like the hated Stealth Rock).

12. Rotom-Wash

Rotom-Wash Pokemon

Rotom-Wash looks like - A washing machine with a Fleshlight attachment.

Rotom recently found a starring role in Pokémon Sun & Moon, where he became the new Pokédex. Most players are already sick of looking at its stupid face, that now takes up most of the bottom screen of the 3DS.

When it comes to battle, Rotom has numerous different forms that are based on household appliances. The most popular of these is Rotom-Wash, which turns it into a washing machine. This change also grants it the powerful combination of Water/Electric typing.

Rotom-Wash is one of the most effective users of the Volt Switch attack. Volt Switch is a powerful Electric-type move that switches out the Pokémon after it is used. This makes Rotom-Wash an effective Pokémon for throwing out status effects (like Burn, through the use of Will-O-Wisp), before changing out to safety with Volt Switch on the next turn.

11. Tangrowth

Tangrowth stands alone on a town's cobblestone street in a scene from the Pokémon anime.

Tangrowth looks like  - Tangela, after he started smoking weed in college.

Pokémon Diamond & Pearl introduced new evolution forms for several Kanto Pokémon. Magneton, Rhydon, Magmar, Electabuzz and Lickitung could all now transform into a new Pokémon. Tangela also gained an evolution. If you can train a Tangela up to level 40, then it can learn Ancient Power. If they level up whilst knowing this move, then they can evolve into Tangrowth.

Most of the powerful Grass-type Pokémon are actually dual-type, the second type usually being Poison. Tangrowth is one of the few solely Grass-type competitive Pokémon, which grants it protection against other popular types (like Ground). Tangrowth has a range of status effect moves that it can dole out onto the opponent (like Sleep and Poison). It also can have Regenerator, the ability that heals 1/3rd of its health on a switch out.

10. Whimsicott

Whimsicott Pokemon

Whimsicott looks like - The Sheep version of a Super Saiyan.

The introduction of Fairy-type Pokémon in the sixth generation of games shook up the metagame considerably. Dragon and Fighting-type Pokémon now faced a new threat, whilst Steel and Poison-type saw a resurgence in order to counter the Fairies that were running wild on the battlefield.

One of the most dangerous new competitors introduced in Pokémon X & Y was Whimsicott. Before Sun & Moon, Whimsicott was the only Pokémon to bear the Grass/Fairy typing, offering it unique advantages/weaknesses in combat. When a Whimsicott has the Prankster ability, it increases the speed of all its non-damaging moves. This makes Whimsicott one of the fastest support/status effect users in the game. It also possesses powerful Fairy-type attacks (like Moonblast) for when it needs to fight.

9. Exeggutor

Exeggutor Pokemon

Exeggutor looks like - The palm tree that escaped from the special bus.

Exeggutor recently saw a revival in popularity, due to its ridiculous new Alolan form. Alolan Exeggutor gained a huge neck, as well as becoming a Dragon/Grass-type Pokémon. Exeggutor has had various appearances in competitive play, with its viability changing from generation to generation.

At no point was Exeggutor stronger than when it was in Pokémon Red & Blue. Psychic-types were the undisputed kings of the first generation (due to them only being weak to Bug-type Pokémon). As Exeggutor is Grass/Psychic, it had access to some of the best moves in the game. It can throw status effects at the enemy and back them up with moves like Psychic.

Exeggutor was considered essential back in the old days, as it was one of the few Pokémon who could reliably take down a Chansey. If Exeggutor used Explosion, then it would knock out a Chansey (as well as the Exeggutor itself). This prevented many turns of trying to hit that tricky egg.

8. Shaymin

Shaymin Pokemon

Shaymin looks like - A Chia Pet.

Shaymin might be the least threatening looking Pokémon in the series. It's hard to imagine that cute little fellow putting up much of a fight. Shaymin is the kind of thing that you paint on the wall of a nursery. It's not something you use in battle against a Mewtwo.

This might come as a surprise, but Shaymin is actually a legendary Pokémon that was introduced in Diamond & Pearl. This means that Shaymin has great stats, as well as unique access to a move called Seed Flare. Not only is Seed Flare a powerful Grass-type attack, but it also has a 40% chance of lowering the enemy's special defence stat. It is also possible to turn Shaymin into its Sky form (through the use of the Gracidea flower). Shaymin-Sky is a fast and powerful Pokémon, who will tear through most other legendaries that dare to face it.

7. Jynx

Three Jynx Pokemon

Jynx looks like - Mr. Popo, if he became a contestant on RuPaul's Drag Race. 

At last! We can talk about Jynx without bringing up the whole controversial design thing.

In Pokémon Red & Blue, Jynx is what is known as a "Glass Cannon". They have high attack and speed but lack defence and HP. Due to Jynx being an Ice/Psychic-type Pokémon, she has access to several powerful attack moves. Her use of Blizzard makes Jynx one of the few reliable counters to Dragon-type Pokémon in the first generation of games (except for Articuno, who is banned in competitive). She can use Psychic to destroy most other Pokémon in the game. Jynx also has access to a unique move - Lovely Kiss. This move has a 70% chance of inflicting Sleep upon the opponent.

Once Psychic-type was balanced out in Pokémon Gold & Silver, Jynx fell out of use. In the first generation of games, however, she could steamroll through the competition.

6. Smeargle

Smeargle from Pokemon

Smeargle looks like - the kind of person who stays up all night drawing Pokémon erotica on DeviantArt.

Smeargle is the definition of a gimmick Pokémon. It is a Normal-type Pokémon with terrible stats. Under normal circumstances, this would relegate Smeargle to being caught once in order to fill up the Pokédex, before being thrown into the PC box forever.

It is lucky for Smeargle that it is the only Pokémon in the game who can learn Sketch. Through the use of Sketch, Smeargle can learn almost every other move in the game.

Here is how Sketch works, it will permanently copy the last move used by an enemy Pokémon. This will replace Sketch in Smeargle's move list. Smeargle can learn Sketch again (and will have the opportunity to do so every ten levels). This gives Smeargle a frightening level of utility in battle. Through the use of Sketch, you can bring in moves like Dark Void and Sacred Fire. To say nothing of the combinations of status/entry hazards that can be brought to bear against the enemy.

5. Jellicent

A pair of Jellicent, as seen in Pokemon Black & White

Jellicent looks like - the balloons at H.R. Giger's birthday party.

With over 750 Pokémon across the series, it is becoming increasingly difficult to find ones that have a unique type. One of the few Pokémon to still be unique is Jellicent (as well as its pre-evolution form, Frillish). Jellicent is a Ghost/Water-type Pokémon. This grants it specific defensive qualities that made it a popular choice in competitive play.

When Jellicent was introduced in Pokémon Black & White, it quickly became known as one of the best counters to Fighting-type Pokémon in the game. The fifth generation of games was when Fighting-type started to become popular in the competitive scene. Jellicent was the perfect way of stopping a dominant Fighting-type, as it is immune to those kinds of moves. Jellicent also had very high defensive stats, as well as a few decent status effect moves (like Will-O-Wisp) to take advantage of the turns the opponent will waste trying to take this balloon down.

4. Abomasnow

Abomasnow standing and looking fearsome in the Pokémon anime

Abomasnow looks like - Dr. Zoidberg had a kid with a pine tree.

Ever since weather effects were introduced in Pokémon Gold & Silver, players have found ways to make use of the unique effects that are brought out by them. Lots of Grass-type Pokémon become stronger when it is sunny. Sandstorm can deal damage for eight turns (if the Pokémon who summoned it is holding a Smooth Rock at the time). Some Pokémon (like Castform) can even change forms depending on the weather.

One of the most effective weather-users is Abomasnow. When it is summoned to the field, it will bring on the Hail effect, which will deal damage to all Pokémon that are not Ice-type. Hail also has another powerful trait. If a Pokémon uses Blizzard whilst Hail is in effect, then it will gain 100% accuracy. Blizzard can also hit both of the opponent's Pokémon in a Double Battle. This gives Abomasnow a very powerful group attack with which to open battles.

Abomasnow is also one of the most powerful Ice & Grass-type Pokémon in the game. If you use his Mega Evolution form, then he will gain a huge boost to his attack stats.

3. Ambipom

Ambipom Pokemon

Ambipom looks like - A purple monkey dishwasher.

Despite what the anime has taught us, most Pokémon battles generally don't last longer than a few moves. The exception to this are players who use stall tactics. In which case the quickest way to end the battle is to punch them in the face for being so annoying.

With matches being so short, it is important that a Pokémon is fast enough to act first. When Ambipom was introduced in Pokémon Diamond & Pearl, it was one of the fastest creatures in the game. Due to its incredibly high-speed stat, most people would use Ampibom as their first Pokémon in battle. He would essentially get a free turn with Fake Out (causes the enemy to flinch, but can only be used on the first turn). Ampibom can quickly retreat from a battle with the use of U-Turn or Return. This makes it the ideal Pokémon for scouting. You can use Ambipom to stall, as the other player reveals the Pokémon/moves they are using. You can then switch out to something with an advantage, whilst keeping Ambipom safe.

2. Klefki

Klefki, a Pokémon that looks like a key ring, in the anime.

Klefki looks like - the Pokémon Company is running out of ideas.

It seems that every generation of Pokémon has its lazily designed Pokémon. There was Voltorb/Electrode, Vanilluxe, Pineco and Luvdisc, to name but a few. The most recent addition to this group is Comfey, the "it is essentially a Hawaiian Lei with a face drawn on" Pokémon.

The most notorious of the lazily designed Pokémon is Klefki. With so many household objects waiting to be turned into Pokémon, why was a keyring chosen first? Klefki is one step away from the Chair Pokémon or the Grout sealant used on bathroom tiles Pokémon.

Don't let Klefki's terrible design fool you, this Pokémon is a beast on the battlefield. Due to its great typing (Fairy/Steel), coupled with its high defensive stats, Klefki is a tricky Pokémon to knock out on its own. You then have to take its status effect moves into account. Klefki can have the Prankster ability (which speeds up non-damaging moves). This makes it easy for Klefki to throw out Confusion effect moves (like Swagger) as well as Paralysis (with Thunder Wave). It is very difficult to even get a hit in on Klefki during battle.

1. Pachirisu

Pachirisu wearing a crown Pokemon

Pachirisu looks like - a cheap knockoff of Pikachu.

One of the most famous quotes in the Pokémon series belongs to Karen of the Johto Elite Four. Once you beat her, she has this to say.

"Strong Pokémon. Weak Pokémon. That is only the selfish perception of people. Truly skilled trainers should try to win with their favorites"

While this is a nice sentiment, it sadly doesn't hold much weight in the competitive scene. There is a handful of Pokémon that are better than the others and that's what everyone uses. If you want to be the best, then you better stick to a team made of Pokémon like Garchomp and Gengar.

One player managed to break the cycle of boring team selection. The 2014 Pokémon World Championships was won by a Korean player, named Se Jun Park. He put Pachirisu, one of the most forgettable Pokémon of the fourth generation into the team that won the tournament.

The current Pokémon competitive format exclusively uses Double Battles (2 vs 2). Se Jun Park trained a Pachirisu to have high defence stats. When it entered battle, it used the Follow Me move to force the enemy to target the Pachirisu, rather than the other Pokémon on the team. This allowed Pachirisu's teammates to deal all the damage, while he acted as a damage sponge. With this surprise tactic, Se Jun Park won the final battle.

Se Jun Park finally proved that you can be the best, like no one ever was, with a team of Pokémon that you like, rather than the ones with the best moves or the highest stats.

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