I think this is called binary trading and the thing is that you are gambling on the very short term of the price of anything like bitcoins, gold, silver, and other assets. I am not sure, however, on how legit these games are to be honest. How do you even know that the movement is indeed that way? It's not that easy to tell if it is indeed going up and down at some point of time, since it is so zoomed in to reflect probably each trade that happens.