Movie
Description
Jessie's Gourgeist began as a Super-Size female Pumpkaboo, a rare, large specimen encountered when she emerged underground beneath Jessie's feet in a Kalos forest. Jessie captured her instantly with one Poké Ball throw. This Pumpkaboo quickly joined Team Rocket's schemes, battling with moves like Leech Seed to ensnare foes and Shadow Ball for attacks. Her showcase debut in Coumarine City featured a scarecrow theme but earned few votes, leading to elimination. She later competed in the Pokémon Sky Relay, winning her leg by hiding inside an Altaria, though her team faced disqualification after Meowth interfered.

A turning point came at the Gourgeist Festival. Count Pumpka, seeking a mate for his Prince Pumpkaboo, proposed a trade, impressed by her size and rarity and offering a Mega Evolution-capable Mawile. Jessie reluctantly agreed. However, during the trade, Pumpkaboo evolved into Gourgeist. Prince Pumpkaboo lost interest, and Jessie—recalling her Pokémon's loyalty, like nursing her through illness and celebrating her birthday—demanded a reversal. Count Pumpka returned Gourgeist while letting Jessie keep Mawile, forging a strong mutual bond.

As Gourgeist, she excelled in Pokémon Showcases. In Anistar City, she used her internal light as a spotlight for Jessie's dance and created fireworks with Seed Bomb, securing third place. Her pivotal role came in the Couriway Town Showcase. Collaborating with Wobbuffet in a freestyle performance, she employed Leech Seed vines, aerial maneuvers, and combined Shadow Ball and Seed Bomb fireworks, earning Jessie her first Princess Key. Gourgeist later helped Jessie reach the Top 4 of the Kalos Master Class.

In battles, Gourgeist faced Ash's Pikachu immediately after evolving but was defeated. She participated in conflicts against Team Flare, using Seed Bomb for smoke screens during escapes and battling adversaries like Druddigon and Weavile. During the Kalos crisis involving the Giant Rock, she helped clear roots obstructing Ash and Alain. After Kalos, Gourgeist resided at Team Rocket HQ before a brief return in Pokémon Journeys, aiding a scheme to capture Ash's Raichu with tactics like signal relays and coordinated attacks.

Her known moves are Leech Seed, Shadow Ball, Frustration, Dark Pulse, and Seed Bomb, all learned as Pumpkaboo and retained. Personality-wise, Gourgeist mirrored Jessie's energetic, dramatic style, enjoying showcases and demonstrating loyalty. She displayed childlike traits, changing vocal tones during attacks and dancing in battle, though she could become temperamental when distressed, like during the attempted trade.

Gourgeist holds distinctions as Jessie's first Grass-type Pokémon, her second Ghost-type, and the first main character-owned Pokémon with a confirmed form difference (Super Size). She is also the second main character Pokémon to evolve via an on-screen trade.