CLICK THE GREEN FLAG TWICE. Arrow keys to move and space to pick up and drop things (just the diamond) and down arrow to slide. Avoid lasers and spikes, blah, blah, blah. IMPORTANT: You can jump through black things (it looks like bad scripting but it works for the game) In the boss after one minute you will receive a hint and after two minutes you will be told how to win. You are a thief trying to steal a giant diamond. Don't die.
I added a timer. Dying takes 3 seconds off your time, so... don't die. It's possible to win, I did it. I won with 42 seconds left (on purpose), then played again. 46. Also, if you have say 1:5 it says 1:05 now! Yay! But NOW, it's HARDER! NEW LEVEL!!