Leonardo is the leader of the ninja turtles with his name being based on Leonardo DaVinci (everyone on the team has names of artists from the Italian renaissance). The character is differentiated by his blue mask and because he has two swords as weapons, in the comics they started out as normal swords, but as the cartoons changed them to changed to katannas they became katannas in the comics too. The character has a rivalry with his brother Rafael, because Rafael is a rebellious character so, of course, he would have problems in a situation of doing what the leader wants.