8th Nov 2013
So Near, Yet So Farfetch'd - S1-E47
Continuity mistake: When Team Rocket takes off in the boat, it sinks. Their pokeballs float away, and Jessie says "Arbok and Lickitung are floating away!" But she doesn't catch Lickitung until Princess Versus Princess (Season 1, Episode 52).
Suggested correction: It's because these episodes were aired out of order.
That's true because of Electric Soldier Porygon.
8th Nov 2013
Continuity mistake: Jessie seems completely surprised when she's told that Voltorb can explode, but in The Ninja-Pokemon Showdown (Season 1, Episode 32), not only did she and the others find out what Voltorb are, they were all affected by the explosions as well.
1st Nov 2013
Pokemon, I Choose You! - S1-E1
Continuity mistake: When the capsule containing the three Poké Balls first opens up, you can see the names of the Pokémon etched into the balls (in Japanese), but when Ash picks them up, the names are gone.