Growl decreases the enemy's Attack strength. Effects are cumulative for
a maximum of six uses. Further uses have no effect.
Note that since the victim's Attack statistic is altered, only Physical
attacks, such as Swift and Dig, will be weakened. Damage caused by Special
attacks like Psychic and Solarbeam will be unaffected.
For more information on the different kinds of attacks and how damage
is determined for each of them, see the Attack Base Explanation.
Despite being a Normal type attack, it is effective against
Ghost Pokémon.