Pretty much what the title says either Pokemon you like that others doesn't seem to like much or Pokemon you think gets way more attention then they deserve.

Charizard: While it's not a bad pokemon it seems to be everybody and their grandmothers favorite pokemon and I don't see what is so good about it compared to other starters.

Personally I like Typhlosion which I feel is a bit underrated compared to other fire starters.

Pikachu: I shouldn't even have to explain why don't get me wrong I do love Pikachu but I feel it's so overrated and feel kind of sorry for Raichu which I think has a really cool design.

Also some pokemon I think are really underrated would be:

Parasect: It has a solid attack stat and can deal some damage with moves like x-scissor or seed bomb and it has a really nice move in spore.Though it isn't exactly competitive material (though I guess it could be with trick room support) it's certainly a nice pokemon in game and gets underestimated a lot.

Shuckle: It's a really fun pokemon to mess around with as it has so many options being so bulky and having moves like power split, acupressure, double team and ability like contrary means it has a lot of fun options to choose from.

Dunsparce: Paraflinch....Nuff said.

Jynx: While barely any people seem to use it because of disliking it's appearance It's actually a pretty good with pokemon with a really nice special attack stat and pretty good speed it can deal some damage with moves like blizzard and psychic and also has some nice coverage moves available and just a pretty nice move pool in general. While it's not the best pokemon it definitely is really underrated.

Arceus: While not exactly underrated competitively a lot of people seems to dislike it compared to other legendaries. I think it's a really cool pokemon with a cool design great move pool and stats and it's ability to change types by using plates is really cool.

Kecleon: Speaking of changing types Kecleon has a really interesting ability in color change which basically changes it type to the one of the move it was hit by last which is a really cool and sometimes fun and useful ability.

I'm probably forgetting some Pokemon but if I was to talk about every Pokemon I feel is underrated or overrated I would just keep rambling on and on these were just some of them from the top of my head.

Anyways what are some Pokemon you feel are underrated or overrated? I'm interested in hearing your opinion on the matter please say why you think a pokemon is overrated or underrated instead of just listing a bunch of pokemon without providing any reason why you think they are underrated or overrated.

The Charmander evolution line is way overrated in my opinion, it is a great Pokémon but is OU.
Many Pokémon are overlooked such as dunsparce,zubat, and many more even though overlooked Pokémon are not always great, but have good qualities and abilities.
Most dragon type and fairy types are OU where normal type are overlooked except for a few.
Many Pokémon need evolutions to make them even an okay possibility for a team.

Overrated: Arceus  All too good stats
Underrated: Shuckle  Amazing defense, with proper training is boss!

I think bug and poison-type Pokémon's are very underrated.. I personally like the Poison-types the most, especially Muk and Grobat.

I have seen lot of people who looves Charizard and this it's the most powerful fire type there is.. I think that's horse poop.

So what is my answer? Most underrated: Bugs and Poison-types.

Overrated: Most of the legendary Pokémon's, even thou they are "legendary" that does not mean you can't beat them with some common Pokémon like Butterfree or Tangela... And of course not just Charizard but another starters are very overrated too.. I personally does not even bother to train my starters anymore, I just use them as long as I get something different and ditch them to my PC after that.

Overrated pokemon: 

As for overrated, definitely pokemon like charizard and mewtwo, not to say that they aren't good, strong pokemon, but people make it seem like without them, they won't have an alternate fire/flying or psychic pokemon. There are plenty of other alternate pokemon out there that are just as good and are underrated, but I think that these 2 take the cake for being most overrated. 

Underrated pokemon: 

I fell like for some reason crobat and poliwhirl are underrated, poliwhirl has a huge movepool and it isn't too bad of a pokemon when it evolves into either Politoed or Poliwrath. And as for crobat, this pokemon's speed is amazing and it has a pretty good type combo in my opinion. Other people may disagree of course, but I think that some people are so obsessed with one pokemon, they are unwilling to explore any other alternatives...you never know...if you took a break from your precious charizard, you might just find something better! XD

Well overrated pokemon are kind of a lot. for one Charizard is overrated by a ton of people. I mean it is an amazing pokemon but nobody ever choose blastoise or venasaur anymore because charizard is just the best in too many ways.
 
 Mewtwo: Well Mewtwo is used in every online battle I do in pokemon X and Y. I mean don't get me wrong Mewtwo is awesome but it's mega evolutions are just too overrated. Halfly because they can easily be taken down by toxic or something.
 
 Lucarrio: Well Lucarrio is self explanitory. 
 
 and a ton more.
 
 Underrated
 
 Almost no pokemon are underrated because the ones that are have no potential at all.

Overrated Pokemon: Pikachu, Charizard, Lucario, Arceus, Magikarp, Goomy

Underrated Pokemon: the bug type Pokemon, the poison type Pokemon, Dunsparce

I just wanna insert my 2 cents about Pikachu. It's the series mascot, it's supposed to be super hyped, well know, and loved by the fans. Nintendo, Game Freak, they all purposefully boost Pikachu. Because it's the mascot, saying it's overrated is basically the equivalent of saying any is mascot overrated. 

Halleck : I still think It's kind of strange to use Pikachu as a mascot but give it an evolution who IMO looks cooler and is more useful but then end up giving Pikachu the light ball which basically makes Raichu obsolete as the only real reason for using it is if you can't get your hands on a light ball or if you like how it looks more.

I feel like Blissey is an incredibly underrated pokemon. She's amazing in combat considering her HP can reach a total of (I think) 711. With the highest health state in the game she can tank so much damage and then just use softboiled to heal up afterwards. 

Great pokemon for any party.

While I haven't found a thread for listing my least favourite Pokemon I will say that this particular one is in fact also overrated... for its cuteness. And that is Jigglypuff. How is that annoying pink brat the favourite cute Pokemon of so many? In the Pokemon it's always there to ruin the day and see, it even tried to kill Team Rocket! 
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I think Pokemon like Blaziken and Thundurus are overrated, as they are so overused, they are in the Uber tier. I think underrated Pokemon like Swampert and Ditto need some more attention.

Overrated: charizard, pikachu, eevee
underrated: magickarp

I think it's a little over rated. They have over 30'000 games an they all seem the same to me. but some how all fun to play.

Overrated: Most of the existing legendary Pokemon.

Underrated: Magikarp. 

Overrated Pokemon

-The entirety of the Charmander evolution lines. Yes, they are good Pokemon, but everyone talks about them as if they had the best stats in the world. Yes, it has a cool design, but there are Pokemon with better ones. It's an amazing Pokemon, don't get me wrong, but it's way too overrated.

-Pretty much every single Legendary Pokemon.

-Lucario. Pretty much goes my argument with the Charmander family with this.

Underrated Pokemon

-The Zubat Family. Everyone talks about them (especially Zubat) like if they were the worst Pokemon ever. Yes, they are common, very common, but they are very good Pokemon. They may not have the best stats or move-sets, but they are still very good. (In fact, I have a golbat in my most recent play through of that is my most powerful Pokemon.)

-Grimer-Muk. Good Pokemon, very good. Poison types have always been cool in my opinion, and this Pokemon has some pretty decent stats and all. They are very underused and seem to feel like they are stepped on.

Pikachu is the most overated Pokemon ever especially when Team rocket tries to steals him.  Most of them he behaves like some little kitty.

Mewtwo is the most underrated  in my opinion. The best pokemon movie was the first one and it's because Mewtwo personality and abilities were so cool.

For underrated, I'd have to say Rattata/Raticate. 

I always try to get myself one early on in the game, and with either Hyper or Super Fang, and Return. By the time I face the Elite, the Pokémon in question is pretty formidable on my team.