Ash's Pidgeot (Master)

Ash's Pidgeot was the second Pokémon caught by Ash Ketchum in the Kanto region, and his third overall.

Kanto
Pidgeot was originally a Pidgey in Viridian Forest, and Ash had decided to capture it. He used Caterpie and then Pikachu to battle it, before capturing it. Pidgey then assisted Ash in finding his Metapod, displaying loyalty immediately upon being caught.

As a Pidgey, he was mostly used for finding things and for his aerial abilities. Upon evolving into a Pidgeotto while saving some Pokémon, Pidgeotto was used more frequently.

Pidgeotto's first gym battle was against Sabrina, and battled Sabrina's Abra who was surprisingly powerful. Pidgeotto managed to land a powerful Steel Wing attack that led Ash to victory. Pidgeotto was then used to battle Erika's team, and defeated her Weepinbell and Gloom.

Pidgeotto was also used to battle Koga, using his Gust attack to repel any poisonous attacks. Pidgeotto participated in Ash's gym battle against Giovanni, and was the first Pokémon to defeat one of Giovanni's and was what led Ash to victory.

Pidgeotto evolved into a Pidgeot while protecting Ash from a flock of Fearow and Spearow, and drove them off. Ash released him to take care of Viridian Forest, though he gave his Pokéball to Professor Oak to keep.

Personality and characteristics
Pidgeot was extremely loyal to Ash and had a strong relationship with him, never once disobeying him or being on bad terms before or after capture. Pidgeot was incredibly brave and would do tasks that would cause injury to himself, and many characters have pointed out Pidgeot's loyalty.