I tried martingale on the new website(luckyballs.io) and it is working with a chance 81.8% and multiplier 1.21x 
of course its working for a few bets though if you would do it for a long time you would loose your whole balance, also shouldnt you do x5 as possibilty to win is 80 per cent? 5x is 80%? 80% win only gives 1.21x multiplier