yes. If your riolu evolves after level 37 it will not learn aura sphere. lucario learns aura sphere at lv 37
You are not able to get Aura Sphere as a TM unless you hack. If you can't/do not want to hack then you will be still be able to get it the harder way. You can get any legendary (discluding Arceus) and level it up to level 100. When it gets to level 100 it will learn Aura Sphere. Lucario learns it at Level 34. Palkia, Dialga, and Giratina learn aura sphere at level 90.
How does riolu learn aura sphere in pokemon diamond version?
you can teach him aura sphere by ging to PWT near driftveil city and talk to this girl and she could make Lucario learn aura sphere.
If you mean Aura Sphere, then yes.
27 my lucario learnt aura sphere lv37
No, it cannot.
Mewtwo learns Aura Sphere at level 93.
Lucario learns Aura Sphere at level 51.
Lucario learns aura sphere at level 37.
it can learn aura sphere at lvl 37
you have to evolve riolu into lucario then keep leveling up until you learn aura sphere.
I'm afraid you can't. Only Lucario can learn aura sphere. Sorry!
you need a modest natured riolu to learn aura sphere or you can use your action replay
on level 90