deskgameClaim your online casino’s welcome bonus. deskgameChoose your state and fill in the required fields, including BetMGM bonus code NJCOM1500 or BetMGM bonus code NJCOM200. deskgameClick the ‘Sign Up’ tab on the Hard Rock Bet Casino landing page. deskgameAt the time that I was playing, the Grand Jackpot for Thundering Horseman at BetMGM Casino was at an incredible $72,448.09.