Mario & Luigi - Bowsers Inside Story
Taking place , you guessed it, inside King Koopa himself, Boswer's Inside Story is a role-playing video game that was published by Nintendo and developed by AlphaDream for the Nintendo DS. The game was first announced at Nintendo's Tokyo Press Event in October 2008 as "Mario & Luigi RPG 3", where they revealed the games plot and play mechanics, as well as the fact that it would involve extensive use of the touch screen.
It is the third game in the Mario & Luigi RPG (Role Playing Game) series and considered by many (including myself) to be the best in the series because of its humor and clever battle dynamic. Released in 2009, Bowser's Inside Story was both a critical and commercial success and by April 2011 the game had sold over four million copies worldwide making it the best selling Mario RPG of all time!