Season 1 from the Pokemon anime is jammed packed full of moments where Pokemon that shouldn't be that powerful are capable of some unbelievable abilities or have been over hyped far too much.
Dishonourable Mention
Any non fully evolved Pokemon that belong to Ash is not counted as that's more plot armour than being over powered. I'm also letting Ditto slide as well.
10. Tauros
I'm starting low as very few people have watched the banned Safari Zone Episode. To sum up, Ash manages to capture 30 Tauros because they kept getting in the way of his targets, in the Gen 1 games, Tauros is likely the last Pokemon you catch, it's stupidly rare and frequently runs away. Despite it's rarity it lacks any decent moveset.
9. Paras
While the majority of it's victories were from Team Rocket throwing fights for it to help it evolve, but then it pulls off a legit victory on Charmeleon with one hit that was by accident.
8. Caterpie
Shouldn't be physically possible for a Caterpie to defeat both Koffing and Ekans, this is where it all started for Team Rocket's downfall.
7. Jigglypuff
Her singing is overpowered, far too often it's become a convenient plot device to retcon the episode.
6. Togepi
Togepi is another Pokemon with a convenient Deus Ex Machina, what doesn't help is that the anime has no clear mechanics for Metronome in the anime.
5. Krabby
The image says it all, keep in mind that was Krabby's first ever battle and evolved shortly after to white wash the whole of Mandy's team. It's never had a major role since.
4. Psyduck
Yet another Pokemon with convenient plot solving powers, Psyduck only adds to the frustration by being infuriating to watch.
3. Sandshrew
Early in the series we see a Sandshrew way more powerful than it should be. Keep in mind the trainer has a reputation for a 100 win streak but even so his backup Pokemon make him the equivalent of Mt Moon trainers at best, this Sandshrew is capable of One Hit KO moves.
2. Bellsprout
Somehow Jeanette Fisher trained her Bellsprout as a Kung Fu master, what really hit it home is throwing and slamming Bulbasaur about and one shoting Pikachu with a single kick which should be physically impossible for a Bellsprout.
1. Gastly
The Ghost of Maiden's Peak really confused matters when it came to Ghost Pokemon. In a number of confusing moments Gastly was able to take on multiple forms including inanimate objects, human ghosts, non existing animals and Pokemon Fusion. Oh yeah it talks as well.
