Level select:
Select the "New Game" option at the main menu, then enter GREYTHERAT as saved game name. All levels, including the bonus levels, will be unlocked. Enter M1A2U3L4!? as a saved game name to unlock all levels until Darth Maul.

Battle Royal mission:
Defeat Darth Maul in level 25 to unlock the Battle Royal mission, where you have to fight eight other Jedi Masters in the Saber Arena.

Additional versus mode characters:
Defeat a character in the Jedi Arena during game play to unlock him or her in versus mode.

Hint: Level 1: Wookie help:
In the introduction to the first level you will see a Wookie resembling Chewbacca walk past Obi-Wan. When the level starts, turn around and walk back the way the Wookie walked. You will eventually see the Wookie standing beside a fire. Walk up to the Wookie and talk to him with Action or Y. Then, continue through the level and the Wookie will follow and will assist you in taking out the Black Heth Thugs.

Hint: Slow Motion Technique
Generally, in a level, the slow motion technice only lasts for about 6 seconds. To make it last the whole level, slow time down. Then, immediatly throw your saber. Always hold the force button, and when time reverts to nomral, wait for your force to drain about a little under half way, and then slow it again. If done right, when your saber returns, and you let go of the force button, you will always be in slwo motion. To get out of this, just slow time again.