http://www.smogon.com/bw/tiers/lc Picking from there.
So essentially, if you could have a single pokemon in real life which ostensibly is not OP like Arceus or Alakazam or Gyarados and would probably just sort of be like your pet, which would it be? For the purposes of this topic evolution can't happen, so they will always be first-stage.
Meowth would be handy for getting money, Growlithe would be the Best Dog Ever, and Psyduck would be adorable. Many of them would be adorable, so I'm honestly torn. Onix would be hard to maintain, so we'll cross that off the list. Trubbish and Grimer and Koffing and Stunky probably wouldn't be too much fun either.
Eh, I think I'd go with Growlithe. Or Elekid if I could use the guy as a permanent power source. Or Ralts to let me teleport.
This is hard.
(Also yes Little Cup wasn't invented by Smogon, I know. But that's easily the most prevalent modern area we see it so yeah.)
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