Promotional Codes' Power: Opening Up Winning Prospects. Many players are not aware that using promo codes, which offer extra money or bonus spins, can greatly increase their chances ofslots games casino winning. The most recent slots winner is a prime example of how strategically using a promo code can result in enormous payouts. It is evident from examining this winner's journey that aspiring players can develop a winning formula by comprehending the workings of online slots & the benefits provided by promotional codes. A Formula for Winning for Future Players.