Get 120 stars with Mario
When you get 120 stars you see a green comet and scatters 120 green stars
There is no easy way
dunnoooooo
If you get 120 stars then you can play with luigi. And then you need to find the 120 stars again but then with luigi!
collect 120 stars with Mario AND Luigi, then go to the trial galaxy rock and go to the backside.
122 power stars and 120 green stars.
120.
First, get 120 stars with Mario. Then, do it again with Luigi. After this, the Grand Finale Galaxy will open on the Trial Galaxies planet.
Yes, Luigi is playable in Super Mario Galaxy. You unlock him after getting all 120 stars as Mario.
120 Green Stars 120 Power Stars 49 Comet Medals Got the game yesterday. Its awesome and EPIC! (Get all these for the Grandmaster Galaxy) source from : Super Mario Galaxy 2 Game Guide by PRIMA Games and Nintendo
To get her as a file icon, you need to get 120 stars and clear the level in Bowser's Galaxy Generator. To get her on Starship Mario, you need to get all 240 stars.