Book of Power Slot by Relax Gaming

Most Book-of-Ra clones give you one tier of Free Spins and call it a day. Relax Gaming built a second tier on top, and the gap between the two is where this game lives. Three Books still trigger 10 spins (4 give 15, 5 give 20) with a single random symbol promoted to Expanding status. Land 2+ of that symbol on a high-pay reel, 3+ on a low-pay, and it stretches floor-to-ceiling and pays across all 10 lines based on count. Standard book mechanic so far.

The twist sits inside the Power Book - a special variant of the scatter that only lands when Power Bet is active or via the mega-tier buy. Three Books with at least one Power Book locked in trigger Power Free Spins instead, same 10/15/20 spin counts but with two upgrades baked in. First, retriggers don't add a second Expanding Symbol like the regular round - they upgrade your current one to the next more valuable symbol up the paytable. Second, every time a Power Book lands on reel 2, 3, or 4, that reel turns golden for the rest of the bonus. A golden reel acts as if the Expanding Symbol always landed there, even when it didn't. Stack three golden reels mid-bonus and the math gets ugly fast.

Power Bet doubles the cost of every spin and bumps the Free Spins trigger chance by 170%, plus it's the only way Power Books appear naturally. The doubled stake only buys frequency and access, not better wins - payouts still reference the underlying bet. If you trigger regular Free Spins under Power Bet, a Gamble option offers a 50/50 to upgrade them to Power Free Spins or lose them entirely. The Buy menu skips the gamble: 100x for guaranteed regular Free Spins, 200x for guaranteed Power Free Spins with the Power Book pre-loaded.

The reels sit inside a sandstone tablet flanked by hieroglyphic pillars, deep Egyptian temple backdrop in dim torchlight. Pharaoh's mask is the top symbol at 500x for five, then warriors and scarabs, then card royals rendered in metallic gold. Once an Expanding Symbol upgrades to Pharaoh and lands fully expanded, it pays 500x ten times over. The multiplier cap on the Expanding Symbol upgrade chain is 9x. Max win: 15,000x.