its for online mode,
first two stages is in the forest, where you fight mostly begginers
and the third to fifth stage is in the battle tower, you will only fight
others who have at least two wins in a row in the battle tower.
simply put, get five wins in a row and you get the achievement.
serously though, it wouldve taken like what, less then a mi***e just to
look at the main menu which pops up when you start the game.

then you have to have online

when you have xbox live you go to online and choose a character