Pick a Pokemon and one move from its debut level up move pool to be a part of the series since the beginning and see how it will change things up.
>you can't pick mono steel/dark/fairy types
>picking a dual type steel/dark/fairy will make them monotype of the other type, for example picking Metagross will make it mono Psychic until gen 2
>you can't pick moves that only have item related effects like Trick or Fairy/Dark/Steel moves
>Special will always be the higher Special Stat between the two

I choose Dusclops and Shadow Punch

Hp: 40
Atk: 70
Def: 130
Special: 130
Speed: 25

>gen 1
It would be one of the top 5 OU pokemon, while Ghost has no effect on Psychic in gen 1 it still would be a better Gengar (albeit much slower) without a weakness to Psychic or Ground, it would also be a hard Tauros counter being immune to normal type attacks and with no real weakness besides Gengar's Lick, it would be only dragged down considerably by its slow speed and hp

With access to Ice Beam/Calm Mind/Hyper Beam/Earthquake/Psychic/Rest TMs it wouldn't even need to run Shadow Punch unless to counter Gengar or double team buffed non normal types

>Gen 2
>Sp Atk: 60
>Sp Def: 130
Misdreavus tankier and better, now with a real weakness against Shadow Ball run by many Normal types it wouldn't be the king it was in gen 1 but still a good OU or top tier RU pokemon just not on top 5 anymore

Which one would you choose?