Lucario

Lucario is a bipedal, canine-like Pokémon with predominantly blue and black fur. It possesses a short, round spike on the back of each forepaw, in addition to a third on its chest. It has red eyes, a long snout, and ears. When its mouth is open, two pairs of pointed teeth, one in the upper jaw and one in the lower, can be seen. It possesses cream-colored fur on its torso and blue fur on its thighs that resemble shorts. It has a medium-length tail of the same blue color as well. It stands on its toes rather than on its entire foot. Lucario has four black appendages that hang down from its head, which rise when it reads or manipulates aura, a special energy that it senses.

Lucario can study auras to predict the movements of its opponents and track their quarry. With sufficient training, it can read auras to understand how living beings are feeling from more than half a mile (1 kilometer) away. It can even use this ability to sense invisible foes. However, it sometimes ends up learning information that it would not like to know, causing it to get stressed out easily. It also has the power to manipulate this energy in an offensive manner, such as in the form of explosive spheres of energy. Lucario can understand human speech and has been reported to communicate with humans through telepathy. In Pokémon Adventures, it was even shown to be able to stop its allies from an Aegislash's mind control using its aura. As shown in Pokémon Horizons: The Series with 's Lucario, a Shiny Lucario emits yellow aura as opposed to the standard blue-colored aura emitted by other creatures. In Super Smash Bros. Brawl, Lucario's eyes glow golden (instead of blue as in the anime) when using its aura vision. Lucario is considered to be prideful and is extremely loyal to its Trainer. It also seems to have a natural sense of justice, as it only trusts Trainers with righteous hearts. It is an exceptionally rare Pokémon that usually lives deep in mountains very far from people to improve their skills. Lucario are primarily carnivores, hunting their prey in packs, though one was seen eating Berries and plants like roses. It has also been seen eating chocolate, which is not part of its natural diet. In Pokémon the Series, it is shown that Lucario can create a staff in the form of a bone to use in battle. As mentioned in the Pokemon Sleep, Lucario never lowers its guard, even when sleeping. It is believed that it reads the auras of others while asleep similarly to when it is awake.

Forms
Lucario can Mega Evolve into Mega Lucario or Mega Lucario Z.

Mega Lucario
As Mega Lucario, its blue fur becomes teal blue, its cream fur becomes longer, and its thighs slim down. Mega Lucario's arms appear more muscular and it develops more spikes on the back of its paws, which have turned deep crimson. It also develops spikes on both of its feet, which have become crimson too. Its previously red eyes take on an orange tint. Its aura-sensing appendages grow longer, and two of them are tipped in crimson. Its shoulders also possess a spike each. Black markings appear all over its its body.

Mega Lucario is believed to be the first discovered Mega-Evolved Pokémon. A legend told at the Tower of Mastery claims that a Trainer and a Lucario found the first Mega and Key Stones and unleashed the world's first Mega Evolution. After the discovery of Mega in the Hoenn region, Mega Lucario was instead believed to be the first Pokémon to Mega Evolve in Kalos. Its aura heightens throughout its body and forms black markings across its blue fur along with the intermingled energy of Mega Evolution. Mega Lucario readies itself to face its enemies by focusing its mental energies. Its fighting style has been described as heartless due to it being bathed in the explosive energy of Mega Evolution, which awakens its combative instincts and causes it to mercilessly attack its opponents.

Mega Lucario Z
As Mega Lucario Z, parts of its body — namely its head, ears, arms, thighs, and tail — turn a dark gunmetal gray, while its forearms and legs turn completely teal. Its eyes turn bright blue with thick black outlines around them, and its face is decorated with an elaborate, silver pattern consisting of circles and crescent shapes. This silver pattern circles the back of Mega Lucario Z's head and extends halfway into its head appendages, which are clumped into two instead of being separated as four. These appendages grow out to reach Mega Lucario Z's knees, and have zig-zag seams on their sides and zig-zag tips at their ends. Two long strands of blue hair with zig-zag tips extend from behind Mega Lucario Z's head and over its ears, which have silver crescent patterns on them. The cream fur on Mega Lucario Z's torso is longer but flares to its right side at the bottom, unlike on Mega Lucario where it forms its tail. Mega Lucario Z's tail is split into two at the tip, and more silver stripes circle around its waist and thighs. Finally, the chest protrusion on Mega Lucario Z is round and shield-like with an S-shaped seam instead of pointy; similar round metal protrusions occur on Mega Lucario Z's hands, shins, and feet.

Mega Lucario Z's powers are said to greatly surpass those of a regular Lucario. It is named as such to differentiate it from the previously discovered Mega Lucario. It uses the longer fur surrounding its head and waist, along with its fan-shaped tail, to visually disorient opponents in close combat. This makes it difficult for them to see its aggressive movements. Additionally, parts of its fur have been hardened with steel energy. By focusing its strength into these hardened areas—specifically the back of its hands and shins—it can deliver powerful blows despite its appearance. It can utilize its powerful aura in various ways, such as extending it into a thin shield or concentrating it into specific parts of its body, like its legs or fists, to enhance its attacks. While Mega Lucario channels its aura into a destructive force, Mega Lucario Z uses it in a more defensive manner by cloaking itself in it to increase its defense, flexibility, and agility, allowing it to parry any attack. In doing so, it battles as if it was gracefully dancing.

Evolution
Lucario evolves from .

(Source: Bulbapedia)