Unearth cosmic secrets in Book of Anunnaki, an adventure slot set amidst ancient Mesopotamian ruins under a vast desert sky, where enigmatic entities hold the key to untold fortunes. This 5x3, 10-payline game features the powerful Book symbol, serving dual roles as both Wild and Scatter. Landing three or more Book symbols initiates the highly coveted Free Spins bonus round. Before these spins commence, a random regular symbol is selected to become a special expanding symbol, covering entire reels whenever it contributes to a win during the feature. The expanding symbol mechanic in the free spins can lead to massive full-screen wins, offering substantial payouts for brave explorers of this ancient alien mystery.