Quote from: btc-raffle.com on December 18, 2015, 02:19:34 PM

Ok try this pretend you know the winning number. Say its 6000 can you show me how to get that number please?
Because its random when you buy a ticket.

If the ticket numbers were assigned to players randomly it would be easiereven trivialfor the house to cheat, not harder, because the house could simply "randomly" assign the winning ticket to a player it controls. There would be no way for players to verify that the tickets were indeed randomly allocated in your current system.

Instead, however, tickets appear to be split among players sequentially in the order in which they entered the game, as can be seen here.

This means it is not trivial for the house to cheat, but not terribly difficult either. Depending on the approximate number of players the house expects to join the round it will add its "puppets" at different points.

Let's assume that by counting how many players are currently online, how many participated in the last round and how many are able to participate in the next round, the house predicts that between three and seven players will join the round. Making accurate predictions within these bounds is fairly easy with the information the house has at its disposal.

Now the house waits for three legitimate players to join. If there are unexpectedly less players, the house simply passes and allows the round to end. If, on the other hand, three players A, B and C enter the round, the house will immediately also "purchase" tickets with three players D, E and F; which it controls, giving player D the winning ticket. Up to four additional legitimate players E, F, G and H can now join without the house losing the winning tickets.

Based on the houses earlier prediction, more players joining is unlikely. But even if an eighth legitimate player defies all odds and joins the round, causing the legitimate player E to now own the winning ticket, the house can simply add another eight puppets, giving the winning ticket back to the house and allowing more legitimate players to join without endangering the house's winning ticket. For all practical purposes this can be repeated as often as necessary. Alternatively, the house can simply prevent new players from joining the round past a certain point, for example by simply ignoring entries and blaming it on latency or bugs.

Such a winning strategy exists for every possible winning ticket.

TL;DR: The house can take advantage of information asymmetry by adding one or more fake players and thereby cheating the legitimate players of their winnings.