What level does Lucario in Pokemon diamond learn metal claw?

Answer 1

Lucario learns metal claw at the very start. i think that means that you should evolve riolu while it's still at lvl 1. It is possible because you can keep it at the very beginning of your party and make it super happy at the daytime.

Not really like that,if you want Lucario to learn metal claw,then have these requirements:Heart scale (Find and Bring plenty with you),Lucario (Around lvl 30-35 and lastly HM Fly.

Ok,so if you have HM fly on a flying Pokemon (I doubt that you would have 1),use fly and fly to Pastoria City,after that,look around until you see a house with a fat (Im going to call him cuz he looks fat) next to the window and the water.So,enter that house and talk to that man,he'll say some stuff then after he says you came to me to tudr your Pokemon,it shows you a list of moves,look for Metal Claw,press A and there (If you have 4 moves already then delete a move) you have now have metal claw.You can do this alot of times when your in need of a new powerful move...

Hope this works,P.S I found this out by my self