"When Magikarp evolves into Gyarados, its brain cells undergo a structural transformation. It is said that this transformation is to blame for this Pokémon's wildly violent nature."
Gyrados is one of those Pokemon that you both love and hate. Because when you have it, you love it. But when you face it? You hate it. Gyrados is a very powerful Pokemon, and has been used by many a trainer, Gym Leader, and Elite Four member over the years, and to this day, it's still one of the most desired Pokemon to get. Which is why people tolerate getting Magikarp.
Gyrados' Basic Attacks are Bite and Dragon Breath. While it's Special Attacks are Dragon Pulse, Hydro Pump, and Twister.