I just recently found this website and I thought I should share.
I've bet few times and won a couple of times too. They seem to be paying out and I'm pretty sure the odds are in your favor, depending on how much BTC you have.

Have a look www.bitvsbet.com

Every day you can bet on 2 different things by sending your BTC to a specified betting address. So you become group A or group B. If at the end of the round (each day) your group bet the most money, you win a portion of the money of the loosing group. According to how much you put in of course.

There's a transaction fee, so be careful with that though. If you win and don't bet much, you might get less than you put in if you don't pay attention to the fee, since it gets subtracted from your winnings. Still, it's not really a big deal if you bet a "sane" amount of BTC.

I highly recommend trying www.sunvsmoon.ml
It's a betting site that actually pays out. You bet either sun or moon and the site resets and pays out every 2 hours. There's some btc in both sun and moon at the beginning of every round, so you can be the only one who bets and still get money.

If you bet 50% of the total winning sum, you get 50% of the money accumulated from the loosing group. (minus a 1% fee)
I recommend betting big at the end of the round so you get an edge or getting a bunch of friends together so they can all bet so you don't have to risk loads of money and still win.

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