Both of his first bets come back as winners, paying him out an extra coin, each. The next few rounds, his luck seems to hold steady, breaking even, before he starts taking losses. A few more tosses, and he actually ends up breaking even, back to the twenty coins he started with. Still, given that the lowest roll always loses, and if the house rolls the maximum, all the players lose, it's definitely a game that's weighted, slightly, in favor of the house. That, and the house's die seems to be slightly mis-weighted.