Description
Satoshi's Pikachu, also known as Ash's Pikachu, is an Electric-type Pokémon obtained by Ash Ketchum as his first partner. This Pikachu consistently refuses to stay inside its Poké Ball, preferring to ride on Ash's shoulder or head. It exhibits a determined personality, sharing Ash's passion for battling and demonstrating leadership among other Pokémon when Ash is absent. Known for curiosity, intelligence, and protectiveness toward younger Pokémon, it notably cared for Misty's Togepi.

Pikachu maintains a strong rivalry with Raichu, its evolved form, battling Lt. Surge's Raichu early on and later an Alolan Raichu. Despite opportunities, Pikachu repeatedly chooses not to evolve using a Thunder Stone to prove its strength unevolved, a trait later mirrored by Dawn's Piplup. The Gigantamax Factor in its DNA prevents evolution even when exposed to a Thunder Stone.

Its known moves include Thunderbolt, Quick Attack, Iron Tail, Volt Tackle, Electro Ball, and Electroweb, and it has improvised techniques like "Revolving Thunderbolt." Pikachu activates the Static ability, potentially paralyzing opponents on contact.

Across regions, Pikachu forms close bonds with Ash's teammates like May's Torchic and Brock's Mudkip. During the Hoenn arc, it temporarily suffered electric buildup illness and amnesia due to Team Rocket but recovered with Ash. In Alola, Pikachu gained the ability to Gigantamax, altering its appearance to resemble its original design while increasing size and power.

In the "Pokémon: The Arceus Chronicles" special, Pikachu accompanies Ash, Goh, and Dawn to investigate Arceus legends. They uncover and thwart a Team Galactic plot threatening the world, with Pikachu participating in confronting the crisis.

Pikachu's bond with Ash originated when Ash shielded it from Spearow, establishing mutual trust. Their relationship evolved into an inseparable partnership where both consistently protect each other. Pikachu acts as a constant target for Team Rocket's capture attempts, though their plans invariably fail, often due to Pikachu's electric attacks enabling escape.

Pikachu exhibits allergies to Cutiefly and Ribombee and dislikes having its tail pulled or being closely followed. Its design changed from an initially chubbier appearance to a slimmer build from Generation II onward, though the Gigantamax form revisits the original aesthetic. As Ash's sole constant team member, Pikachu participates in multiple Pokémon Leagues and contributes to Ash achieving the title of World Champion.