at casino, 80% odds is on house favor. I'm not really like to play at casino, even at landbased casino, i only play in slot.
You saying that the house has a 80% house edge but at the same time you are playing slots which makes up almost 70 or 80 percent of a casino profit is pretty appalling to me. Regarding the strategy of winning in roulette, the only way to win is either get all the numbers possible or list the average number that is likely to win.
Every casino game has different probability on winning it so it is not going to be same for slots and roulette but the rewards will be higher when the chances of winning is lower. And also in any of the casino games there is no way to win until it happens on its own or we can cheat and win which is not possible in online casinos though.