Pocchama, Dawn's Water-type Pokémon, accompanies her alongside Ash and Brock on their journey to Crown City for the Pokémon Baccer World Cup. True to its species, Pocchama displays pronounced pride, instantly puffing out its chest after any stumble or fall. This self-esteem fuels its independent streak, manifesting as a reluctance to accept food or assistance from others.

Throughout the travels, Pocchama actively participates in battles and group endeavors. It joins Ash's Infernape, Brock's Sudowoodo, and Dawn's Mamoswine to repel a group of Vigoroth pursuing Zorua. Later, while navigating sealed-off Crown City with Dawn, the group, and journalist Karl in search of Zorua's caretaker Zoroark, Pocchama remains present. When Zorua briefly escapes, Pocchama gives chase alongside Ash's Pikachu, leading them to a garden encounter with Celebi, where Pocchama witnesses Zorua mimic Celebi using illusions.

Pocchama engages Kodai's forces during the pursuit of Celebi and the Time Ripple. It launches a Bubble Beam at Entei, only for the attack to be dodged. Near the stadium, its Hydro Pump accidentally strikes a wild Onix instead of the intended target, provoking the creature. Pocchama swiftly employs Whirlpool, creating a protective barrier that halts the Onix from trampling Ash. In an earlier skirmish, it attempted Drill Peck against Pikachu, countered by Iron Tail.

A constant presence on Dawn's team, Pocchama reacts to events unfolding around it, including Zorua's shape-shifting antics and the escalating chaos triggered by Kodai's manipulations, without significant character evolution or backstory expansion beyond its established traits within this narrative.