you play the game normally, except pressing space causes that Telestar to pop up. the only way to exit the world 2 boss stage is to use your Telestar. it does nothing afterwards, but you can still take it out for fun. and this game desperately needs a sequel. please make a Bowser battle sequel to save the world altogether. using the Telstar at the boss level causes a glitch that makes the boss stay forever, so if you don't want that to happen, use it on any level before the boss.