>>13949613Specially offensive Lucario is fun to use but, like you said, it's outclassed by physical just because of better priority (Extremespeed) and better coverage options (Ice Punch, Stone Edge, Bullet Punch, etc, etc).
That being said a decent set would be something like this.
Lucario @ Life Orb
Ability: Inner Focus
Nature: Timid/Modest
252 Sp Atk/4 Sp Def/252 Spe
-Nasty Plot (Obvious)
-Aura Sphere (Best Fighting type STAB short of Focus Miss, which you shouldn't be using with Lucario)
-Dark Pulse/Shadow Ball (Fight/Dark and Fight/Ghost have amazing coverage together, it really just boils down to if you'd like flinching or a chance to reduce Sp Def)
-Vacuum Wave/HP Ice (Again, boils down to preference. Priority is always great to have but so is being able to get rid of things without the +2 Sp Atk boost like Landorus-T, Gliscor, certain dragons, etc)
There are other options like Psychic and Flash Cannon but they have redundant coverage with Fight/Dark or Fight/Ghost.
