Defensive Punishment.
I think my play-style most accurately reflects a defensive one.
Early game I use lots of Utilt, shield/grabs, uncharged aura bombs and F-Airs -> whatever. I try to reframe from smashes at this point in the game, they come out far to slow and are gimped in power compared to later match when aura pumps them up. I like to force them to come to me with aura sphere, as they charge in meet them with maybe a high priority Fair to the face or shield their attack opening them up to a hit or 2 from you. Dair is amazing, many players make it a habit to attack from the bottom as most characters do not have many options there, lure them into it, set your self up for what your opponent sees as a opportunity to Usmash, Uair or whatever. I find most players just cant resist going for that golden opportunity to juggle, sadly for them though however, Lucero’s Dair is more then likely going to blast straight through whatever they got (their are a few exemptions however of course.. Zelda's Uair/Usmash is just one I know of)..
As we enter mid-game and Lucario's aura is quite a bit stronger, KOs becomes much easier to score. Now is the time to have aura spheres charged and seek out those openings to connect an Fsmash. Keep your aura sphere charged and keep on the move, dodge right and left from shield to avoid your opponent, punishing them occasionally with short hop aerials or jab-jab-force palm combos, however keep your game making sure to keep your opponent chasing you.
This is when you go for the kill, which Lucario is provided with a few different options to choose from.
Switch from evasion to more punishment focused, as your frustrated opponent is probably trying desperately to make some sort of real contact on this pesky evasive Lucario it's likely he will become more reckless and offenive in mindset, picking up on your preference to evade rather then attempt a stronger attack then his own.
Marth for example, Marth runs in going for a dash attack, expecting you to dodge or maybe shield, surprise him with an Fsmash from a distanced to connect far before Marth's attack is executed and watch as an out-smarted Marth and runs head first into it's long range tip flying to his demise.
Another option for the kill is Double-team, follow as plan from before and stay for the most part on the run, as a kill focused Marth looks for his opening for a nice Fsmash, toy around a bit, then give him his opportunity, dodge right into his sweet spot and hit that down-B double team, chances are he'll take the chance to send you flying with no second thought, however once again out-smarted by mind games, Marth will be sent flying at the smash from a double team hits him.
While I’m on the subject here is a few other tactics I find helpful in my game.
Going off the edge to hit a (for example) Fox attempting to recover with foxfire and hitting him with a quick Fair or Nair if you can will often push him far enough from the edge to KO. Knowing to intercept opponents off the side of the stage is an excellent skill to possess as Lucario and as you get better with it, you'll begin to see many low percent KOs.
Learn to be able to use your tilt's well, it took me a while to do them reliably with out accidentally doing a smash attack instead. Lucario doesn’t have much for speed on the ground and his tilts make up allot of if, you'll benefit an incredible amount training your self to know the right time to use them rather then smashes. For a long time I played default controls, then switched to having control stick jumping off and found it made an amazing difference for anyone who doesn’t already play with it off.
