Shadow Sirens™ is an attractive Fierce Factor™ game that offers players the higher volatility they crave in a beautiful game they will not be able to resist. The PowerXStream® pay evaluation offers players 576 ways to win, and mystery progressives add to the excitement! When at least one Bonus symbol lands on reels 2, 3 and 4 the Free Spin bonus round is initiated. The player will be awarded with up to 128 Free Spins. Shadow Sirens is a game that will not disappoint!