So, we have: Clefable, Wigglytuff, Magmar, Electabuzz, Raichu, Hitmontop/Hitmonlee/Hitmonchan, and Jynx… Btw this is ingame
If I forget a Pokémon please tell.
I think it's either Magmar or Jynx. Magmar has 100 special attack and learns fire punch, thunder punch, and flamethrower. Jynx has 115 special attack and learns ice punch and lovely kiss. Both of them also have a good speed stat. However, catching a wild Jynx from the Ice Path is better than all of these options, simply because this Jynx comes at a higher level and requires a lot less experience to use. source