>>55031832The anime repeatedly stated that Ghost pokemon were super effective against Physic pokemon and that's the very reason Ash goes out to find one (ie Haunter)
MEANWHILE, IN GEN I
>In Generation I, Ghost-type moves have no effect on Psychic-type Pokémon, though an abundance of evidence suggests that this may have been an error. Multiple sources mention that Ghost-type moves are super-effective on Psychic-type Pokémon: official strategy guides published by Nintendo, two episodes of the anime (The Tower of Terror and Haunter versus Kadabra), and even the games themselves, where a Pokémon Trainer in the Saffron Gym mentions that Psychic-type Pokémon "only fear Bugs and Ghosts" (though the reference to Ghost-type Pokémon was removed in Pokémon Yellow). This was corrected in Generation II to make Ghost-type moves actually be super effective against Psychic-type Pokémon. 