How to Unlock
Lucario
•  Play 100 brawls
•  Beat Target Smash!! on all difficulty levels (Playing in either 1 or 2 player mode will satisfy this condition.)
•  Get Lucario to join your party in The Subspace Emissary
•  With the exception of the last of the three methods listed above, you’ll need to face Lucario in a brawl and beat it after satisfying the above conditions to unlock it.