I played Sackboy up to rank 200 and I can say he's really good. He can also be a really annoying person,the basics of Sackboy is to always set up the teleporting door I think it's Triangle Down. I usually use it to avoid supers,I put it high high in the air usually. Second off,always have the electric panel next to you. Sackboy has the best super level 3 in the game in my opinion,because free AP,items,and it's easy to kill them because they can't evade. Sackboy's hit confirm is also the electric panel so that's also important,only use his level 2 when in a crowd. Remember to practice his Square and Triangle Up they are also very useful. If you want quick AP,go to the far end of the map,put up the fan and spam the Jam ball or Cakeinator.
All I can tell you
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