The Book of Ra is one of the most famous slot machines available first on land casinos and now also avaialble in online casinos as Book of Ra Deluxe. It is themed around ancient Egypt where you are on a quest to find ancient Egyptian Gold. The game uses an expanding symbol feature which fills all three slots increasing your chances of winning.
The Wild symbol of the Book of Ra also doubles as a Scatter. This means that, it will substitute other symbols to create winning combinations as well as generating its own payline when 3 or more symbols are aligned, Free Spins mode is activated when 3 or more of the symbols show up on the reel (regardless of the bet lines active). During the Free Spins, a symbol between the regular ones becomes expandable: If this symbol appears at least 3 times, it will extend to cover the roller entirely, while the value of the winning combination is multiplied by the number of pay lines. If during this mode Scatters appear on 3 other reels, you enable additional 10 bonus games.