Such gambling games are useless and wastage of time. I personally don't like to even explore such webs. This isn't only wastage of time but extremely wastage of money for no reason. Instead, you can use ETH for a good purpose and can vote on Mainnet if this could support it. This way you can make more coins rather than losing for every bet. I don't think that people should take a high risk. On the other hand, sharp-minded and wise people can play this gambling game to double up the current amount.