Yoshi Topsy-Turvy arrived for the GBA with a new way to control the action. In his attempt to stop Bowser's mischief, Hongo the Great Book Spirit sealed him in a pop-up book, along with Yoshi's Island which is where Bowser was located at the time. The Spirit who loves Surprises showed up and told Yoshi there is a way to bring Yoshi's Island back.It's up to Yoshi to save the day in Topsy-Turvy. You will travel through 6 chapters in this pop-up book, each containing numerous stages. You will have to tilt the world to help Yoshi climb walls, open new paths, and send enemies rolling away. You will earn Happiness Medals that will allow you to move on to the next chapter if you clear certain objectives that the Spirits ask of you.Along the way, Yoshi will be transformed into a ship, a ball, and a balloon. With the tilt sensor, this is a platform game like no other on the GBA.