Welcome User This is a Multiplayer "The Lost Diamonds" game there are lost diamonds behind the black screen you have to find atleast 6 green diamonds and then the black diamond to win the game.
When you will eat diamonds your speed will be increased but their are some poisoned diamonds which will reduce your speed so be carefull.
Every diamond has a specific spot from where you can eat them its tricky.
You have to press the keys again and again to walk on the screen, the more quickly you presses the keys the faster you will walk.
Every time you eats a diamond the black diamond will be repositioned on the black screen. Which means it will be lost again. So its a real lost game :p Best of luck