For this bonus Riobet offers 40% match bonus along with free spins on Secret of Atlantis slot. The bonus requires a deposit of 20€ and for every 5€ you get 1 free spin. This bonus isn't automatic and you can claim it in the cashier after you have made a deposit that qualifies for it. In my case I deposited 30€ and got 12€ bonus and it requires only 35x bonus wagering . First I went to play my spins and unfortunately I won only a couple of cents.
Then with 42€ balance I started to play Twin Spin. With minimum stakes my balance was going up and down but quite soon I hit a dry run and left the game when I had 20€ balance left. With that I started to play Flowers slot. I played with 0.30€ bets per spin and my only big win was from a small 5oak win on base game, I had no luck and couln't trigger any free spins. So at last, with only 5€ let I went to Drive slot. I played with 15 cent bets an soon triggered free spins round that paid me almost 60x bet winnings. Then I decided to increase bets to 0.30€ but I couldn't get any more bonus features and ran out of credits eventually.
Overall I had a really nice playtime at Riobet casino. There are many things I like about this casino and this bonus was one of them. And since it can be claimed once every 7 days, I am sure I will be visiting them soon. I had no technical issues and no problems claiming the bonus and the game selection and wagering makes it really irresistible for me.