The first Mario Galaxy had the excellent idea of sending Mario in space and this episode follows this simple and effective formula. The levels are comprised of a series of small planets to cross and gravitation is a central element of the game. Move from one planet to another requires avoid traps, monsters and to address evidence in Deck passages.
In short, Super Mario Galaxy 2 improves all aspects of the first episode. The inventiveness of the planets and situations never stops and trouble was (slightly) revised upwards. Yoshi, classic character in the series, is now playable in several levels. Finally the 240 star - twice as much as in the first Galaxy - scattered across fifty levels allow to play more than a hundred hours to complete the game 100%.
As reproach note the reuse of elements of the first episode, even if it means playing two games in a row to realize. The game may also seem a little too easy and linear for the regulars of the old 3D episodes.
Super Mario Galaxy 2 is a very good episode of a timeless series satisfy gamers of all ages.