Book Of Oil operates on a 5x3 grid with 10 fixed paylines. Wins form by landing matching symbols on these lines from left to right. The Book symbol is key, acting as both a Wild and a Scatter. As a Wild, it substitutes for all symbols to help form winning combinations. The Scatter role of the Book is crucial for triggering the game's main feature: Free Spins with Expanding Symbols. Keep an eye out for the Oil Tycoon symbol, which is among the highest paying in the game. The game’s high volatility means you might experience longer dry spells, but the potential for big wins is there when the features hit.

The betting range in Book Of Oil spans from €0.1 to €45, accommodating both casual players and high rollers. Given the high volatility, consider starting with smaller bets to extend your session length and increase your chances of hitting the bonus features. The Bonus Pop feature provides a direct path to the Free Spins, but weigh the cost against your current bankroll to ensure it's a worthwhile investment.