• English / United States: Professor Kukui's Lucario
• Japanese / Japan: ククイ博士のルカリオ
• Japanese (Romanized) / Japan: Kukui-hakase no Lucario
• Japanese (TL) / Japan: Professor Kukui's Lucario

Professor Kukui's Lucario was revealed when it was used against the Shiny Guzzlord that was threatening to take over Alola just like the other Guzzlord did in Dia's world. Later, it was sent out to battle against Ash in the Exhibition Match.

Alola League Exhibition Match

Kukui’s fifth Pokémon to battle in the Alola League Exhibition Match was Lucario. Lucario can concentrate its mental energy into a mysterious wave called aura that can reduce boulders to dust. Ash's Naganadel was the one tasked with matching up against Lucario. Wicke commented that she never could imagined an Ultra Beast would bond with a Trainer and take part in a Pokémon battle. Naganadel’s X-Scissor missed completely and Lucario’s Close Combat caused real damage as a quick follow up.

Throughout the battle, Naganadel was very open to Ash’s guidance as he had been showing it the real meaning of friendship since it was Poipole and it was now battling on Ash’s behalf. Naganadel used Sludge Bomb but Ash forgot that Poison-type attacks are completely ineffective against Steel-type Pokémon. In terms of offense, defense, and speed, everything Professor Kukui's Lucario did in the battle was in perfect balance but they made a critical mistake as Ash imitated Kukui in the way he battled. Since Lucario wouldn’t let them land any attacks like they normally do, they switched strategies with the circumstances and met head on with an X-Scissor which clashed with Close Combat but then Naganadel used Dragon Pulse very close and scored a big hit to knock out Lucario.