Lucario is a jackal pokemon, who, along with David "Snake" Thatcher, helped found Blue Team, which was originally a small neighborhood peace-keeping group, that later became a national organization, and the strongest protectors of Earth. Lucario was a quiet, kept-to-self kind of person, and did not like to talk about things that bothered him with others. He only talked about such things with Snake.
He was stong and determined, and was never a coward. In fact, Lucario was famed for his bravery, fighting spirit, and constant determination. He was tactically brilliant, and always kept a cool head, regardless of the situation. Lucario, along with most other members of Blue team, was a firm believer in the god Anurel, and did not forsake his religion under any circumstances.
Under Lucario and Snake's leadership, Blue Team rose from being a small group of crime fighters based in Providence, Rhode Island, to becoming the most famed and powerful defenders of the world, and they saved the world many times over, beginning an era of peace that, at the end of Blue Team's days, lasted for decades. For his exploits, Lucario was taken up into Aetherius by the Divines themselves. His fate following this is unknown, but many believe he became a god.
Lucario, one of the two founders, was friends with Snake since the beginning, way back in time, all the way to 3rd grade. They met, and became the best of friends. Never had one single fight. After graduation from RIT (Rhode Island Tech Univ), crime was clearly a major problem in their neighborhood. Once he re-united with Snake, they decided to make an organization that would act against this crime, and restore order to all of Rhode Island as a long-term goal. They named this organization Blue Team. For about a month or two, Blue Team was solely the two friends.