Super Mario Galaxy
Completion bonuses
After getting 120 stars as Mario, you will see an alternate ending. After the credits, you will get Luigi and a Luigi Icon. Luigi is just like Mario, but he jumps higher, runs faster, and has lower traction.
Grand Finale Galaxy
After you get 120 stars as Luigi, you will unlock the Grand Finale Galaxy for both Luigi and Mario, where Star 121 is found after all 100 purple coins are collected.
Assistant
Use a second Wiimote during game play. Although a second player will not appear, the second Wiimote will have its own pointer.
View number of lives lost
Collect the final star in the Grand Finale Galaxy with both Mario and Luigi. The information for your saved game file will now include the number of times you have lost a life.
Homing attack
Spin in mid-air then immediately press Z to hit the nearest target.