Book of Helios features a classic 5-reel, 3-row grid layout with 10 fixed paylines. Wins form by landing matching symbols from left to right across these paylines. The game is set against an Egyptian backdrop, with symbols including traditional hieroglyphics and the hero, Olivia Brave. The Book of Helios itself acts as both a wild and a scatter, substituting for other symbols and triggering the game's main features. The payline structure is straightforward, but the potential for big wins lies in the special features and expanding symbols.

The betting range in Book of Helios spans from €0.1 to €100, accommodating both casual players and high rollers. Given the high volatility, players should be prepared for longer sessions with potential dry spells, but the reward can be substantial. The Buy Feature offers a shortcut to the Free Spins, but it's important to weigh the cost against the potential returns, especially in free play where managing your virtual bankroll can still enhance the experience.