Question

If I can catch it?
Where can I catch it?

Answer 1

In Chllenger Cave, you can catch a Riolu. Evolve it into Lucario by leveling it up during the daytime when its happiness is maxed out. Or... you could trade. Hope I helped!

Comments

thanks :) but where's challenger cave?

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The Challenger's Cave is an area within Route 9 which does not open up until you have completed the Elite Four. This cave was designed for strong trainers to come in and train their Pokémon against high-levelled wild Pokémon and a variety of strong trainers. It is collapsed in the time of Pokémon Black 2 & White 2

From Serebii

Answer 2

lurcario can not be found but riolu can be in challenger's cave