God, too many. Not sure I've got the time to write them all up but here's a few off the top of my head.
Yeah, Cloyster got popular when it could abuse Skill Link + Icicle Spear, but I liked it long before then; back when all it was known for was access to Spikes & Rapid Spin and being the butt of various unfortunate female anatomy-related jokes. Cloyster has always been a favourite of mine; I'm not sure why. Maybe simply because it's badass; the Pokedex tells that its shell is so strong it can withstand a bomb blast. And that's reflected in its colossal Defence stat. I'm weirdly entranced by Pokemon with massively unbalanced stat spreads; Cloyster's super-high Defence leaves its HP and Special Defence distinctly lacklustre, so it's never been an all-round tank.
It's also always been a Pokemon that tended to get rare and unusual moves, especially in earlier generations. Rock Blast and Toxic Spikes are rare among Pokemon not of their respective types; Barrier and Clamp are bad, but oddly stylish; and Explosion is always a cool option. It even gets Teleport and Tri Attack in Gen I for whatever reason.
Yeah. Real men use Cloyster pre-HGSS.
In a world where Salamence, Garchomp, Hydreigon, Kommo-o, and Baxcalibur roam free, Kingdra has always been an incredibly underrated Dragon. It seems to get overlooked a lot.
Kingdra is in the same boat as several of the Johto gym leaders' signature Pokemon - in that when you fight it it seems insurmountably tough, and then when you catch one yourself it turns out to be fairly underwhelming. When I first fought it in Gen II, it seemed insurmountable - like it had no weaknesses at all. I had to resort to Electric moves and hope that'd work. But even despite Kingdra's fantastic typing and the fact that it's largely gotten better and better options each generation - Swift Swim, Sniper, Dragon Dance, Outrage, Hurricane, Iron Head, and it actually benefited from the physical/special split really well - it feels like it's never really lived up to its potential.
The whole Horsea line is a favourite of mine and I'm glad it got a cross-gen evolution so soon. I really like this mon, and always love using it.
One very pretty birdie. I loved Oricorio from the first moment I saw it - a form-changing bird representing all of Alola's islands is such a neat idea.
The Baile form is indisputably my favourite (as a European, very happy that it's our regional); I'm not hugely into the other forms - Pom-Pom and Sensu are alright, but the Pau'u is utterly dreadful. But look at how beautiful the Baile form is! Elegant, sultry, and the shiny is phenomenal.
Plus Dancer is a sick ability. Feels incredibly broken that it doesn't cancel or override your intended move, so you can attack or use Protect or whatever else, and still get a boost as well! Utterly wild. I made a Ribombee/Oricorio Doubles team for the Battle Tree ages ago and it was great - really should go back and invest some more time into that to try and get a decent streak. It got me to Blue, but I know I can do better than that.
Even without nabbing loads of Dancer boosts it's not terrible - on its own it's more than good enough to be a great contributor to any team. But I'm quite in love with it. Cool design, cool mechanics, cool mon.
Five in one. It's well-known in my local Pokemon Go group that I'm a big lover of bugs, particularly the funkily-coloured shiny ones. And I have a lot of favourites. Snapshot round, let's go!
Mothim? On paper this thing looks it should be fantastic: decent offensive stats, Tinted Lens, and Quiver Dance! Has enough variety to put together a decent movepool; it absolutely has the potential to be a decent player in the lower tiers. And its shiny is legitimately in the top 10 in the series. That royal blue is simply gorgeous.
Ledian? The bruiser with no muscle. I love that it's all about punching and being a spunky little scrapper and yet does not remotely have the stats to back that up. But it's always learned some great moves: Ice Punch, Psybeam, Dynamicpunch, Reflect, Baton Pass. The fact that it has an absurdly high Special Defence tickles me. People (especially on here) write this bug off, but I've used it in Johto, Hoenn, and Orre and always been pleasantly surprised by what it's managed to accomplish. Plus it's way cuter than that fucked-up monstrosity Ariados.
Shuckle? Literally so much fun to use. It's one of those Pokemon that's either hilariously easy or downright impossible to beat, with absolutely no middle ground. And for something so specialised there's all sorts of fun shit you can do with it. Toxic-trapping? Rollout? PP stalling? Boosting with Shell Smash and Contrary? Turning it into an absolute physical wrecking ball with Power Trick? Yeah, go nuts. I love Shuckle very hard, always have.
Masquerain? Oh boy does this thing slap. Intimidate is such big dick energy on an early-game Bug-type. That said, it's unlikely you'll be getting it as an early-game Bug because hahahahahahaha 1% appearance rate in RS, totally absent in Emerald! God, how much I wanted this thing back in the day before I finally got my hands on one. It's just so cool. Should have stayed Water/Bug, but it gets so much mileage from having briefly been that type: breed Hydro Pump onto it and watch your enemies quake in fear. Giga Drain is nice as a further method of wrecking Rock-types who want to stop you in your tracks. 10/10 Bug mon, Quiver Dance just made it all the more impressive.
Crustle? So cute! Genuinely adorable. Truly the best of Unova's bugs. Yes, absolutely! And it learns Rock Wrecker! Come at me with your Volcarona, I will quite literally shoot you down.
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I'll probably think of more later.