Chespie/History/Main series

Chespie made its first appearance outside the Mega Evolution Specials alongside Mairin in A Meeting of Two Journeys!, at Lysandre Labs. Alain called Lysandre for an update on the situation, only to be informed that nothing had changed at the time.

It appeared again in The Synchronicity Test!, where Mairin sent Alain a video of her and Chespie. Though Chespie had shown no signs of improvement, she assured Alain that the two of them were fine, and told him to do his best. Lysandre claimed that Alain could revive Chespie by collecting Mega Evolution energy. In truth, Lysandre had no intention of helping the Spiny Nut Pokémon; the energy was actually to power a machine to influence the mind of Zygarde. After Lysandre's true colors were exposed, Mairin set out to rescue Chespie from Lysandre Labs, with the help of and. Chespie was eventually rescued in The Right Hero for the Right Job!. However, it ended up absorbed by Lysandre's fallback plan, a Giant Rock with the appearance of Zygarde 50% Forme, in Rocking Kalos Defenses!, although it was eventually rescued by and Alain in Forming a More Perfect Union!, temporarily halting the Giant Rock. The energy was absorbed by the Giant Rock, and as a result, Chespie finally recovered. Squishy thanked it before leaving with Z2.

Chespie reappeared alongside its Trainer in Battling With a Clean Slate!, where it received a medal from Professor Sycamore for the heroic efforts against Team Flare. In The First Day of the Rest of Your Life!, it danced with its Trainer and Alain.

It appeared again in Till We Compete Again!, where it was standing by Mairin's side.