Super Mario Galaxy

Mario's adventures are among some of the finest video games ever made, and Super Mario Galaxy is certainly no exception.  Usually Mario has to just save the princess, but this time the stakes have been raised, not only has the princess been kidnapped again, but the entire universe is in danger of falling victim to Bowser's tyranny.  

Official trailer

Tips, cheats, secrets

Cosmic races boost start

To get a boost, you'll have to press several buttons in sequence during the "3, 2, 1" countdown before the race. When the countdown begins, hold forward, then press "Z" when the countdown reaches 2, then press "A" when "GO!" appears. This will give you a huge boost!

Super ground-pound

Try performing a ground pound during a spin attack. First set up the normal ground pound, then shake the Wii remote and as you spin press Z.  This will cause Mario to spin around in the air, then home-in on any nearby enemies with a ground pound.  

Unlock Luigi

Collect all 120 Power Stars and defeat Bowser to play through the game again...except as Luigi! Luigi controls slightly differently than Mario; in fact, the differences mirror those in Mario All-Stars' Lost Levels. In short, he jumps much higher (making some puzzles easier), but he has less traction, so he slides around a lot more.

121st Star

This star is the 121st and true final star in the game, found in the Grand Finale Galaxy. To unlock it, you must get all 120 stars and defeat Bowser with both Mario AND Luigi. Once you do, you can access this galaxy from the Planet of Trials, in the center. Just speak to the Luma to launch off to the galaxy. As for the mission itself, see the Grand Finale Galaxy page for details.

Walkthroughs

 https://www.youtube.com/watch?v=Y1I3-kulxs4&list=PLYpDU5ElRBfm-mGGHxnUboaZBLoAqMl5T

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