Here’s a good (or bad, I guess) reason you might want to pick up a Super Mario Galaxy player’s guide this early, which is what some people have done. This isn’t a storyline spoiler for Galaxy, but it’s a huge revelation involving collection of all 120 stars in the game and what you get for obtaining every single star. No, Yoshi won’t appear to grant you 100 lives. No, it’s not something lame like a slightly different ending.
Now, it’s a given that you’ll fight Bowser at the end of the game. If you choose to go ahead and fight him again after collecting every single star, however, you get a VERY nice little bonus. Pay attention to and after the credits, and you’ll unlock exactly what you can check out after the break. Thanks to Mark for the submission. SPOILERS AHEAD!
When you finish the game, you’ll be able to play through what’s essentially Super Luigi Galaxy. The eternal understudy is finally back and playable in a Mario game! You play through the entirety of Super Mario Galaxy as Luigi, which might not seem like much, but it becomes a very different game. As usual, Luigi can jump higher and farther, and he runs faster but with less traction. The game is supposedly much harder with Luigi, so you’re not only getting a playable platformer starring Luigi, but you’re getting a “hard mode” at the same time!