Book of Oil brings the lucrative world of petroleum exploration to your reels in this engaging 5-reel slot machine. This oil industry-themed slot features 3 rows of symbols and 10 adjustable paylines, offering players multiple ways to strike it rich. The reels showcase premium symbols including a wealthy businessman in dark shades as the top-paying icon. The mysterious book serves dual purposes as both Wild and Scatter symbol, unlocking the game's most rewarding features. Landing three book symbols triggers the coveted Free Spins bonus round. Every winning combination activates an optional gamble feature, allowing brave players to potentially double their profits at Granpampa.