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>hurr durr Dracovish got nerfed
this happens all the time with every pokemon. Their strength depends on what the plot needs them to do. This was Pikachu's battle, so he was going to outperform everyone else no matter which pokémon Ash brought.
Ash could've brought back Charizard or Infernape or Greninja and they would've been defeated almost immediately because the plot demanded for the first pokemon to be taken out quickly so they could focus on Pikachu and Gengar