Duping: Simply Save your character, and import on a new one, or possible the same one, drop the stuff and re-import. Simple as that, but to do this you need 2 characters playing, but if your not simply save your single-player character, play multiplayer, follow the steps above and save it, and there we go! Duplicated items!

Extreme game with previous items: This will start an extreme mode game with the items on a non-extreme save. First start a new extreme game and load the character you want. Then go to change players and start up a new player 2 character. After the 2nd player loads, remove player 1. Once that's done import the character that you just removed into the player 2 slot (A message about importing characters will pop up, just continue). When its done loading you should have the character loaded with all his/her items from that save. Next just remove the player 1 charater and you're done.

Level 10, 45 skill points, 500,000.

Press and hold L1 + R1 + Triangle + Square + Circle + X, Continue holding them and press L2.

Level Warp and Unlimited Health Menu

During play press and hold L1+R1+Triangle+Square+Circle+x then, while still holding these buttons, press START. A menu will appear with options for Unlimited Health and Level Select.