That was very lucky of you then. Twice to hit 9900x would be awesome especially if you have placed a decent amount of bet. Although the next 9900x I think would be hard to hit for you as you have hit twice already in 30k rolls.
and
I used to bet like that with the 999x rolls. Basically you generally are suppose to win once every 1K. And I would basically bet with 0 Satoshis for the first 1000 rolls and then right after bet with like 10 Sats or something because chances are the next 1K rolls has a higher probability of being a win than the last 1K.
Not a bad strategy but takes forever and all bets are indepedant of another and someone you can go on for 5K rolls without any winners.
LOL, those things are one of the most stupid things I have ever heard.
When you gamble (especially on a provably fair website), you need to realize that all rolls are independent. Sometimes you won't hit 1000x in 10k rolls, and sometimes you'll hit it 10 times in a 1000 rolls. However, each spin has the same probability, and is not influenced by previous rolls.