There are a few things that the anime does better than the games. One of those things is giving individual personalities to all of the Pokémon. Bayleef always wanted Ash's attention and worked hard to earn it. Torkoal was always getting emotional and wanted the best for others. Krokorok wore those cool glasses and had a collected personality.
What is your ideal personality for a Pokémon? Do you think the Pokémon are losing their personalities as the show continues? How important do you think personalities are? What team of Pokémon had the most displayed personality? Which Pokémon did the best at combining their personality with their Trainer's? Any compliment or complaint that you have about the personalities of Pokémon can be discussed here :D
I haven't been following the show much for a long time, so I dunno how much truth can be found in the statement that they've lost touch over time. From what I've seen of Piplup, it looked like a tryhard know-it-all who knew absolutely nothing, and I also recall Emolga being super shifty. Granted those could've been isolated incidents.
In XY, Froakie seems to have a lot of determination so far, and Chespin tends to do more thinking with his stomach than any other part of his body, so I'm not quite following the idea they they've stopped doing this. It'd probably be one of the show's greatest sins as it were if they did. Blank slate Pokémon are the worst. Crowd fillers are one thing, but whole episodes centered around a COTD who's Pokémon has all the intrigue of a stone wall is... ugh. I'm not even talking about fleshed out personalities. Anything that shows more life than a battling robot that might eat and run around in circles with Ash's Pokémon would suit me.
Pokémon of the Day episodes tend to handle this better, though.
But overall, yeah, this is one of the reasons I still give the anime proper credit where it's due, because it shows that Pokemon aren't hiveminded, but instead are individual. There's some general rules you can apply to a species, yeah, but I always find it a little worrying when someone feels like a Pokemon can only be defined by a blurb in the Pokedex.
That's like using this blurb in the dictionary as the only defining trait for humans:
humans are the only mammals not endowed with a natural defense against the elements, such as fur or a thick hide
Gee, that's it? Man, why do I get out of bed in the morning if that was all we had that made us noteworthy? Anyhow, point made.
As for which Pokemon had the most personality, from what I've seen of Piplup, it likely would win for being so over the top, but the obvious answer is Meowth. Then probably Psyduck. They little guy tried so hard, and you know he did because he was so dang proud of his pathetic efforts.
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No, I don't think they are losing their personalities. I think personalities are being improved as episodes go by. I like how the anime shows personality in each individual pokemon and brings life into them, something the games never do.