I see md5 hash before bet
http://rollincoin.com/provably_fair_md5.phpI found some info:
What's Next Game Hash?
When you play HEAD or TAIL, our system show the winning BEFORE you begin to play, and displays the result on the page in an encrypted way, called Next Game Hash, for example e3d609a53bfe3c59db30813e6a65273a (It means that we had your result before you place your choice).
For each game we generate a randomized key, of 26 characters long, for example 4f68e3a6f93bf4208457634aa7, then we organize the winning face and the key like this: HEAD/4f68e3a6f93bf4208457634aa7 or TAIL/4f68e3a6f93bf4208457634aa7 and we calculate the MD5 hash of this string. In our example, the MD5 hash of TAIL/4f68e3a6f93bf4208457634aa7 is 41799624d9e08e4552843c32aa96fc4b, so the results of the game must be HEAD.
MD5 is a strong encryption algorithm that cannot be broken today and where each MD5 string matches with one unique non encrypted string. You can find MD5 generators here.
That last statement isn't true... MD5 is a weak encryption algorithm that can be broken today, and each MD5 string can match with an infinite number of unique non encrypted strings (just like any hashing algorithm, including SHA256).
This description does not match the procedure executed by the site. The string hashed is not HEAD/<26 characters>, it is "win" or "lose", a colon, and the decimal representation in plain text of the secret key. Not sure where you found this text, but it doesn't describe this game.
This site requires that you browse the provably fair page to see the next game hash. If someone else plays, your hash is taken. Also, those displayed hashes have changed on at least two recorded (and independently verifiable) occasions, rendering the entire "provably" part irrelevant. The site has already been positively identified changing hash listings after a wager is received. View the wayback machine to see that the listed hashes have been changed from the posted hashes.
Even if the system presented were actually fair (it's not), the game itself is not fair because the hashes presented are not always the hashes of the data played against. This is not provably fair - and actually not fair at all, it will change the result of your bet.
Payment does not indicate "not a scam". Ponzi's pay out until they run out of money, but they're just as scammy. I have demonstrated mathematically that the system professed by this site is not only unfair and unreliable but also incorrectly implemented in a manner that can only be qualified as "cheating".
Even if the site pays, if it has to cheat to maintain an edge, it's a scam.