Hi! I moved this over to the Pokémon General forum since it's the best place to ask general questions like these!
When I was growing up, mine was for sure Pikachu. I just thought it was so cool, especially Ash's, and really loved it. Then as a pre-teen I started loving Banette a lot and used it often in the games. <3 I still like both but they're not my favorites anymore like they used to be aha.
The people above have some of the best childhood favorites, I relate so well. =')
Just thought of some more: Butterfree, Lapras, Bulbasaur. All of a sudden I'm getting vivid flashbacks to being a kid and pretending to be a Bulbasaur while 'Pokémon battling' my cat at the time lol. poor cat I'm so sorry
Ho-Oh had been my favorite for YEARS! I’d always looked up to my cousin for his video game skills, so I was thrilled when I beat his Blue Version team on Pokémon Stadium 2, wiping out most of it with my Ho-Oh from Silver (which I had named LOVE, under the impression that naming Pokémon after positive emotions made them stronger). I’d had trouble beating Red on Mt. Silver too, but my cousin told me that I could probably beat him now with my Ho-Oh, so I tried again and it worked! Its appearance in the first episode of the anime was also really neat and mysterious.
Oh, it's a toughie. I'll cop to Charmander getting overexposed, but I still wouldn't have gone anywhere without my starter, and Charmander was my favourite of the bunch back in the day. I'm less inclined to pick the Fire-type starter than when I was younger, but you know, every child's got a little arsonist in them ready to break out.
Although there's some stiff non-starter competition. I always felt Caterpie looked cute, I loved that weird-looking Abra and was pretty glad to finally catch one of those (curse your Teleport!), and Ralts immediately grabbed my eye back when I randomly found one back when first playing Ruby.
Tell you the truth, I was never good at commiting to 'a fave' even as a kid. There's a long, storied history of me being asked my favourite film and then freezing up.
Currently trying to beat Sword without attacking. You can read the log and see my progress here.
Always has been, and always will be, Piplup. Piplup (and Empoleon) have a special place in my heart. Piplup was the first Pokemon I ever saw and I thought it was the cutest of the 3 Sinnoh starters, and Empoleon was my first fully evolved starter.
My history with Pokemon is weird since I loved it in grade 1 and dropped it until grade 7 so it's hard to say what my childhood favourite was as a childhood. However, when I was getting back into the series, I LOVED Houndoom and Mightyena because they are both Dark-type dogs and they looked awesome and I've used them both a lot in my XD run and I refused to separate them. Unfortunately to the fault of my own, I've lost both of them and I was sad and even though I have competitive versions of them now they will never replace the OGs.
Back when I only knew Gen 1 as a small child from playing Pokémon Stadium, I was really attached to Persian, Aerodactyl and Eevee! Out of those, Eevee remains one of my all-time favourites. But these days I prefer Pokémon like Nidorina, Ponyta, Lapras, Scyther and Eevee's evolutions as my Kanto favourites.
Two butterflies, we entwine
In petals and silk
Didn't have a strict favourite in childhood (outside of the obvious Pikachu); I only started picking favourites in adolescence. First it was the Sneasel line, then the Litwick line for quite a few years, then the Gastly line, and finally Mimikyu. I do expect Mimikyu to stick around for longer than the rest did though, simply because the little baby has no equal for me.
Since I started with the anime long before I knew about the games my favorites as a kid were always Ash's Pokemon. The two I remember liking the most for the longest time were Tauros and Kingler. I think my favorite one between the two was Tauros.
I specifically remember watching the episodes where I started to think that these two were the coolest/strongest ever. For Tauros it was the Tauros competition episode where Ash's Tauros won and everyone wanted to trade for Ash's Tauros. For Kingler it was the famous Indigo League episode when Krabby evolved and dominated.
Bulbasaur and Gengar used to be favorites of mine a long time ago, but the Kanto overexposure ended up changing that. I remember back when only Gen 1-3 existed getting a Gengar was like a dream for me, but Gen 4 and onwards introduced a good amount of strong Ghost types that I like more.
Having been exposed to the anime, I thought Charizard was awesome. Then when I got TCG, it was Gen III and I got tricked out of my Torchic card...cue getting my first game and although there's no Charizards in sight my starter is a Torchic! So that was my favourite for quite a while, until I finally got far enough into the game to turn it into Blaziken with Blaze Kick, which I just thought was the coolest thing ever.
Since then I keep gravitating towards dragons (except Garchomp) as well as Pokémon from the first few routes in Hoenn. Gen IV was the first time I was aware of new Pokémon in advance and I took an instant shine to Piplup's line because penguins. Likewise Samurott in Gen V.
My favorite Pokémon growing up was always Starmie, mainly because of the anime and Misty using it. I thought it was very interesting. Then, when I started playing the games, I found that Starmie was great in the games as well, so it was great for me.