Sandshrew
Surprisingly, Sandshrew is the only Gen I Pokemon on this list, though there were quite a few others who fell just outside the top ten. I chose to put Sandshrew here instead of Sandslash simply because I like the design a little more: I always thought the brick-like patterning was a really neat idea, even though Sandslash bears a closer resemblance to the creature that inspired this family, the pangolin.

It's been many a year since I used a Sandshrew/Sandslash in-game, but I did once breed a "competitive" Sandslash (not that I compete very often, but it's fun breeding Pokemon and tinkering with movesets). Apparently one of the family's assets in that regard is that they get Rapid Spin to blow away entry hazards, while also being able to make entry hazards of their own. Which is nice.

Corsola
For a long time, Corsola was one of those Pokemon that I admired in principle but never really gave much thought to. I mean, a coral Pokemon is a pretty cool idea, and I'm happy whenever an interesting or overlooked animal gets a Pokemon based on it (yep, coral is an animal, strange as it seems). Plus it's so damn cute it could easily be a talking-animal-sidekick in a Magical Girl show. But I never used one until my SoulSilver playthrough.

My plan had originally been to catch a Marill, but I had failed to realize just how bloody difficult it was to find Marill in Johto. Finding myself in Olivine City, I realized there were Corsola nearby, and so the plan changed. I knew they didn't have much of a reputation for... anything, really, but I caught one with Natural Cure and added her to the gang. In-game, she proved herself worthy, especially after learning Power Gem, and was actually the team member who took down Lance's Charizard, winning me the Pokemon League. Thanks, Corsola! You're awesome.

Competitively, I don't think Corsola gets much of a look-in. Natural Cure is a great ability, and it can get Regenerator from the Dream World, but the consensus seems to be that mediocre defenses and very low speed holds it back. Which I won't necessarily dispute, but come on. Of course it's slow. It's coral.

Zorua
Once again, Zorua is here in its evolution's place simply because it's cuter. In terms of actual gameplay, they can be considered one and the same. I think Zorua's one of those Pokemon that I love almost entirely because of design: its Illusion ability, while entertaining, is a bit awkward to use effectively (though when it does work out as planned, it's fun times all round). I used a Zorua/Zoroark in my White playthrough, and aside from trolling Psychic-types, it's a good, solid Pokemon with strong offense, which is generally what you want in-game. I will freely admit, however, that my love for Zorua might have something to do with its appearance in the opening to the thirteenth movie, escaping from the villains like a tiny adorable badass. Then Celebi showed up and it got boring.

Gothitelle
During the run-up to Black and White, this was the first Pokemon I saw that made me immediately exclaim: "I'm having one of those." Human-like Pokemon can be a bit of a hit-and-miss affair, design-wise. I both like and am disturbed by Jynx, and Mr Mime is the stuff of nightmares. But Gothitelle is just stylized enough to be elegant, and I just love that expression. She looks deeply annoyed to see you.

She's an interesting one to use in-game, because she gets a lot of Dark-type moves alongside the Psychic ones you'd expect, making her your best bet for taking down other Psychics. She's slower and bulkier than you'd think, though her stats aren't massively skewed in any particular direction. Metagame-wise, I hear she can do interesting things with Trick Room, but I've never looked into it that closely. All I can say is that Gothitelle was probably the most reliable member of my Black team, and would be my favorite Psychic type if it wasn't for another Pokemon who I just happen to like that little bit more.

Chikorita
Ladies and gentlemen, I give you: the best starter.

Yeah, I know. Chikorita is a bit of an oddity among the starters: Defense-oriented with a lot of healing and status moves, but a smaller-than-usual range of options for direct damage. This, combined with the Grass-unfriendly selection of gyms in Johto, makes choosing Chikorita akin to playing Hard Mode, particularly in the early stages. That said, if you allow it to be the defense/support Pokemon it's obviously designed to be, Chikorita will be a tremendous asset in-game. The metagame, with its higher emphasis on strategy over raw power, is where the Chikorita family arguably gets to play to its strengths, though. Sure, it's NU, but so are all of the cool Pokemon.

Plus, you know, it's cute.

Whimsicott
Holy balls, this thing is adorable. Look at it jiggle!

It took me a little while to warm up to Whimsicott. I passed on it during my initial playthrough of Black, largely because I already had a Grass-type in Snivy. But it had one of those designs that slowly grew on me until it had surpassed every other Gen V Pokemon in my eyes. Being based on the Vegetable Lamb of Tartary also helps. Instant credibility points there.

I finally got to add a Whimsicott to my team in White, and it didn't disappoint: pretty strong all-round, and faster than God. Type coverage was a bit of a problem, as it's basically limited to Grass and a few Flying-type moves via level up: it learns some good TMs too, but they're the kind that aren't available until the postgame. I'm told that in the metagame, Whimsicott's various status moves and access to the Prankster ability makes it an excellent annoyer in some tier I'm pretty sure didn't exist last time I looked at Smogon.

Mightyena
Mightyena has the misfortune to be placed at the very beginning of a regional dex, just after the starters. This generally doesn't bode well for a Pokemon's stats and viability in the late-game environment. Mightyena has the stats you'd expect from this, but can hang in there nonetheless, even though its native RSE puts its Dark-typing at odds with its physically-oriented stats (remember, kids: in the bad old days, all Dark-type moves were Special for some reason).

I'm just going to come out and say it: The main reason I love Mightyena so much is because it's a hyena, and hyenas are the greatest animals on Earth. Even better, the dex entries about its personality and behavior take their cues from real hyenas, rather than the cartoon villain version we're usually fed. Mind you, it still ends up being one of the Pokemon of choice for RSE's villain teams, but RSE's villains were kind of nuts anyway.

I was always going to end up using Mightyena whether it was any good or not, but it does seem like the physical/special split worked very much in its favor. Gens IV and V do slightly troll Mightyena users, though, by having its strongest STAB move, Crunch, only learnable by the Poochyena stage at Level 53. Seriously? I mean, Poochyena's seriously cute and I can well imagine wanting to keep it unevolved for a while, but until Level 53? Yikes.

Gardevoir
Who'd have thought an awkward-looking kid like Ralts would grow up into such a graceful, elegant... floaty thing?

Gardevoir is a really satisfying Pokemon to use in-game, progressing from Ralts, which can be KO'd by a strong breeze, to something that can hand out astonishing Special Attack damage with one spindly, tapering arm tied behind its back. Yeah, even fully evolved, Gardevoir is about as fragile as it looks, at least in regards to physical damage, but it scarcely matters given that things it encounters tend not to live that long: Gardevoir has a big variety of moves available, giving it excellent type coverage.

And then there's, um, Gallade. Intended to be the "male" version of Gardevoir, except that there are already male Gardevoir, and it still evolves from the super-girly Kirlia, so it just feels like a male Gardevoir who's sensitive about his appearance and overcompensating. Sorry, but it's as ugly as Gardevoir is pretty. Not even Zoey owning one in the anime was enough to make me like it. Evolving a Kirlia into that thing should be classified as Pokemon cruelty.

Miltank
The first great thing about Miltank is that she always looks so happy. She's smiling in every one of her sprites (in Crystal she appears to be mooing in delight) and her HGSS artwork, which has her leaping for joy, might be one of my favorite ever bits of official art. Such a degree of optimism is kind of infectious, especially when it comes from a cow.

Miltank has one of my favorite designs, and it's interesting that she's often considered the counterpart to Tauros, which was one of the Gen I designs I found the dullest. It's not a bad design, it's just a mostly-realistic bull with a few extra bits stuck on. Miltank is supposed to be (in real-word terms) a female of the same species, but look at the contrast: she's as stylized as he is realistic. Now, I think was probably a conscious choice if only for the reason that realistically-rendered dairy cows do not look particularly dynamic or threatening. I'm sure, too, that Tauros has its fans who enjoy that particular kind of design, and fair play to them. But to me, Miltank is much more illustrative of Sugimori and co's ability to take something potentially mundane - a dairy cow, a sea lily, coral - and turn it into something appealing, vibrant and fun.

Gameplay-wise, Miltank is sometimes described as Blissey-lite; she can operate in the same niche, having the same typing and many of the same healing/support moves, but doesn't have Blissey's insane HP stat, instead opting for more balance. But while she's no impenetrable wall, Miltank can actually hit stuff, hard, and is faster than you'd expect of her given her physique. Again, there's more call for support types in the metagame than there is in the main game, and Miltank is one of the Pokemon I really enjoy playing with competitively on the rare occasion I get the chance, because in the right team she can be a defensive wall, an offensive powerhouse and a cleric. No wonder she's so damn happy.

Mawile
It has a mouth in the back of its head.

...

What, you need more justification than that?

Okay. Mawile wins instant nerd points for being based on a cool youkai, the futakuchi-onna. But what I really love is how the concept was turned into a pleasing design. Back in Gen I, Pokemon based on humans or human-like things had a tendency to turn out a bit weird-looking: Mr Mime, Jynx, Hitmonchan, the Machop line, etc. They looked a bit too much like messed-up humans and not enough like actual creatures. You can still occasionally see success this way - I personally like the Gothita line and Meloetta - but it's harder. But the approach taken with Mawile is more sensible: it has humanlike traits, but you'd never mistake it for human.

Additionally, rather than going for a straight adaptation of the myth, the designers have played around with the base concept to come up with something new. The futakuchi-onna's second mouth wasn't generally depicted as large, and it was embedded in the back of the head. In some illustrations, the hair would form tendrils that snatched up food to feed the mouth. Here, the designers hit upon the great idea of transforming the hair into the mouth, ultimately giving Mawile its most defining characteristic: those giant jaws that are an unexpected addition to an otherwise very cute Pokemon.

So how does Mawile play? Well, its stats are so low that you can get nitrogen bubbles in your blood after looking at them. There's a caveat, though: both Mawile and Sableye were given piss-poor stats but unusual typing to make up for them. Sableye has no weaknesses, and Mawile, as a pure Steel-type, has a ton of resistances. They were obviously both intended as Pokemon that couldn't necessarily deal much damage, but would be hard to take down. Today, I think Mawile's forte remains physical defense, but that role is also gradually changing.

In Gen III, the old physical/special system worked to Mawile's advantage. It had three weaknesses: Fighting, Ground and Fire. But it also had high Defense which could be boosted even higher, and with Fighting and Ground moves exclusively physical, Fire was the only thing that utterly destroyed Mawile. On the downside, Mawile's potential for inflicting damage was limited both by its stats and by its lack of a STAB move (though it could boost its Attack with Swords Dance). Come Gen IV, Mawile got its STAB move in Iron Head, but the physical/special split meant that suddenly it had to fear Focus Blasts, Earth Power and all manner of nastiness. Gen V kept this state of affairs but gave Mawile the damage-increasing Sheer Force as a Hidden Ability, thus continuing the trend towards Attack-oriented Mawile. Indeed, in Gen III and IV, Mawile's only real use in the metagame was as a Baton Passer. And this was a huge amount of fun for me, because I found that Mawile and Miltank made a particularly great team: passing defense boosts to Miltank made her into a true wall, while Attack boosts had her demolishing the scenery. But in Gen V I've heard tell of Sheer Force, Attack-based Mawile, and I think this is something I'll have to investigate: seeing my baby doing real damage would be a wonderful thing.

Mawile is one of the most common Pokemon to be brought up when discussion turns to those who most need an evolution. I'm pretty much in agreement with this: Mawile has a lot of interesting characteristics but is held back by sucky stats. That said, I'm a little wary of what evolutions have done to previously cool-looking Pokemon like Rhydon and Magneton, and I just really, really hope that any future evolution of Mawile will be Gardevoir-pretty instead of Gallade-ugly.