Pokemon GO includes some of the most popular and strongest creatures in the franchise, but Magikarp can't be branded either of those terms.
The popular mobile game is still taking over the world, even after all this time. Despite the raging pandemic, Pokemon GO has found a way to keep its status as a top tier mobile experience for fans of the series.
Trainers that have stuck with a Magikarp may know by now, but Gyarados is one of the most powerful Pokemon to have. It takes quite a bit of Magikarp Candy to evolve one into the monstrous Water/Flying-type, but it is well worth it for those wanting to battle or attack/defend Gyms.
Note: This article is subjective and reflects the opinion of the writer.
The best Pokemon GO moveset for Gyarados
Pokemon in Pokemon GO attack differently when they are defending a Gym than they do when controlled by the trainer in battle. They actually attack every two seconds and disregard the speed of the move being used.
This makes a difference when using Gyarados in those various situations. The same Pokemon GO moveset for attacking a Gym or participating in a League Battle is different than the right moveset for setting a Gyarados to defend a Gym.
The best offensive moves for Gyarados in Pokemon GO are Waterfall and Hydro Pump. Waterfall is a solid and fast Water-type attack. It deals 16 damage and generates 8 energy. Hydro Pump costs 100 energy to use, but deals a massive 130 damage. Remember that these both get a Same Type Attack Bonus when used by Gyarados.
The moveset for a defending Gyarados in Pokemon GO changes just a bit. Waterfall will remain the base attack. Instead of Hydro Pump, the Charge Attack will be Outrage. This Dragon-type move deals 110 damage and costs 50 energy. Since a defending Gyarados is not controlled by the trainer, this allows it to release a more powerful attack faster than if the energy for Hydro Pump was needed.