Haunting the back halls of 20th Century amusement arcades, the legendary cursed game 'Deal With the Devil' would appear for a scant few hours, inviting those who came across it to bet their 'souls' on a game of chance. While not unbeatable, the game presented a dark challenge to the unlucky and the unwise. It would appear for long enough to harvest several souls before returning to whatever underworld it had sprung from, though it is rumored that some lucky players managed to 'win' the game, and came away more powerful than they began.
This is a mere simulation, but perhaps it conveys some of the tension felt by those hapless humans who ran across 'Deal With The Devil' in the real world.