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Riley's Lucario (Japanese: ゲンのルカリオ Gen's Lucario) is the primary and, in the anime, currently only known Pokémon owned by Riley.
In the anime
Lucario debuted in Steeling Peace of Mind! at Iron Island. When Ash and his friends traveled there after being contacted by Barry, they found the local Template:Type2 Pokémon fighting brutally against each other and the other Pokémon on the island. When a crazed Aggron attacked Ash, Riley stepped in and had Lucario attack it with Close Combat. Despite being a Steel-type as well, Lucario wasn't affected like the others of its type due to its strong aura.
Riley informed Ash that like his Lucario, he could use Aura. Together they found the source of the problem: A machine operated under Mars's command that was using the Spear Key to create low frequency waves which tortured the Template:Type2 Pokémon. Lucario attempted to read the Aura coming out of the machine, but at that time, Mars placed the Spear Key into a pillar at the ruins the squadron was excavating. The beam that launched out of the pillar's tip overwhelmed Lucario and caused it to rebel against Riley, even breaking its Poké Ball in half when he tried to recall it.
Even then, however, Lucario wasn't completely under the machine's influence and tried to destroy the machine but couldn't do it. Ash managed to finish the job and destroy the machine and Lucario and the other Template:Type2s were brought back to their senses. When Mars realized her plan was shot, she fled and attempted to blow up Iron Island with bombs, but her efforts were thwarted when both Riley and Lucario used their Auras to contain the blast and send it flying.
Moves used
In the games
When the player teams up with Riley at Iron Island, Lucario is the Pokémon he will use in double battles against wild Pokémon and enemy Trainers.
Later, when Riley can be found as a double battle partner in the Battle Tower, Lucario is one of the potential Pokémon he may use, and in Pokémon Platinum, he will use Lucario at the Battleground as well.
At Iron Island
At Iron Island
At the Battleground
Trivia
Related articles
For more information on this Pokémon's species, see Lucario.