HOW MANY DAYS CAN I SURVIVE ON A TINY ISLAND? 

It's Johnny's Island. And the mission is to survive as long as possible until you are rescued. You must catch drift wood in the ocean while avoiding sharks. You must wait until it rains in order to get water. And you must throw spears in order to catch fish. How do you make spears? With the wood you got avoiding sharks, of course. Fun!
I hope Johnny dies