Puck is certainly multi-dimensional. At times we as readers believe that we have a solid grasp on who he reallyis, but I would argue that this is never actually the case. I would say that Puck is a deeply empathetic character, while at the same time being concerned with his own situation. He is also clever and wiley. At times Puck seems almost silly, but at the end of the play, with his final speech, he is given a level of control and his true wisdom comes through: "If we shadows have offended, Think but this, and all is mended, That you have but slumber'd here While these visions did appear."
I'm going to refer you to previous answers to this same questions. Follow the links below; you should be able to find a bunch of useable information.