This full-power attack grows more powerful the less the user likes its Trainer.
Frustration is the move that utilises the Happiness in the negative light, by rewarding the amount the Pokémon hates the trainer. It also is a Normal Type Physical Attack with 20PP and 100% accuracy and its power is calculated by the following means:
Base Power = (255 - Pokémon Happiness) / 2.5
This gives a maximum result of 102 and a minimum result of 1