A high roller is always looking for the best online slots that will give him the biggest payouts when it comes to online slots. Choosing the right slot game can be a challenging task today with so many available. Our list of the best high-roller slot machines reflects this. 1. Mega Moolah World-renowned Mega Moolah is one of the most popular online slot machines. This progressive jackpot game has paid out millions to lucky players, making it a top choice for high rollers looking to hit it big. The game features four different jackpots, each with its payout amount. The…