Big Burger Load it up with Xtra Cheese is a lighthearted take on classic American diner fare. This 5-reel, 10-payline slot from Pragmatic Play features appetizing symbols and a free spins round where the grid can expand up to 8 rows high. With an RTP of 96.04% and high volatility, lucky players can win up to 3000x their bet. Random condiment multipliers and Pop symbols in the bonus add extra winning potential.