The Invincible Pokémon Brothers are a trio of brothers that are villains in the Pokémon series, they use Fighting-type Pokemon, more specifically, the Hitmon-trio evolutions. They appeared as the main antagonists of the episodes "Gotta Catch Ya' Later" and "Cerulean Blues".
The Pokemon Brothers are cheaters who do not follow the rules and resort to dirty tricks. For example, they would have their Pokémon fake being incapacitated and hit the opponent when their guard is down. Another example is in a battle when the battling brother is losing, the other two would send out their Pokémon, resulting in a three-against-one matchup. The Pokémon Brothers are delusional in that they actually believe they are not cheating and will even argue that they won fair and square if their cheating is called out.
In Gotta Catch Ya' Later, they pestered Misty in order to challenge her to a battle. When Kim's Hitmonchan fared poorly against Misty's Politoed, the other two illegally sent in their Hitmonlee and Hitmontop to outnumber Politoed but then, Ash and Brock arrived to even the odds and the heroes managed to beat the cheating brothers. Turns out, The Pokemon Brothers were in cahoots with Jessie, James and Meowth of the Team Rocket trio, only because the TR trio promised them gold, but it turns out that the trio had lied to the Pokemon Brothers. Ash's Pikachu, Brock's Forretress, and Misty's Politoed all attacked the TR trio and the Pokemon Brothers, sending all of them blasting off into the sky.
The Pokémon Brothers reappeared in Cerulean Blues, where they planned to get revenge on Misty. They took advantage of Misty's inability to control her Gyarados, claiming that she is no longer eligible to be a Gym Leader because of this. They then challenged Misty to a battle, with the winner becoming the Cerulean Gym Leader, but the Pokémon Brothers' refusal to fight fairly (Hitmonchan faking to drown and all three using their Tentacruel) gets them disqualified quickly and when they have the nerve to declare that they won "fair and square," Nurse Joy bans them from all official Pokemon league matches for life, the capital punishment for all Pokemon Trainers. In retaliation, the Pokémon Brothers have their Tentacruel attack Gyarados, demanding to be declared the winners and have their ban lifted. When Misty takes the Tentacruel's Poison Sting to protect Gyarados, nearly drowning in the process, Gyarados breaks out of its cage, saves Misty, and sends the Pokémon Brothers and their Pokémon blasting off with Hyper Beam and Hydro Pump.
MembersKim is the red-head and leader of the three, Kail is the blue-haired member of the group, and Kai is the brown-haired obese member of the group.
Kim is known as Chan in the original.
Kail is known as Rin in the original.
Kai is known as Shan or Xian in the original.
In the original version of "Cerulean Blues", their birth-order is stated, with Kai stating that he is the eldest and Kail stating that he is the youngest. By process of elimination, this would make Kim the middle brother.