Return inflicts damage and has no secondary effect. The base power of Return is dependent on the friendship of the user. The greater the user's friendship, the greater the base power. The base power can be calculated using the following formula:
Base Power = Friendship / 2.5
The base power of Return varies between 1 (at the minimum friendship value of 0) and 102 (at the maximum friendship value of 255). The base power of Return is set to 1 if the formula outputs 0. If the user's friendship is 127 or less, Frustration is stronger than Return.
Return does damage depending on the Pokémon's IQ. At no IQ, it does 5 damage. The damage is increased by 5 after reaching 50 and 100 IQ, and every 100 IQ after that, until it deals 45 damage. Although not possible under normal gameplay, IQ of 1000 or higher makes the attack instantly KO.
In the Spanish version of the games prior to Generation VI, Return is called Retroceso, which is likely due to a direct translation of the word return. An accurate translation was given in Pokémon X and Y, where the move was renamed Retribución.