A book slot with two bonus personalities

BGaming released Book of Hidden Tombs on August 20, 2026. An Egyptian temple, a travelling explorer and jewel-toned symbols establish the theme, while the ten-payline structure gives the base game a recognisable book-slot foundation. The special Book carries both substitution and bonus-trigger responsibilities.

The publisher states 97.00% RTP, high volatility and a maximum win of x10,000 the bet. Its separate progressive-multiplier limit is x512. These figures should be read together with their roles: x512 belongs to the Super Free Spins mechanic, and x10,000 is the overall stated payout ceiling.

Official specification

• Developer: BGaming
• Release date: August 20, 2026
• Paylines: 10
• Published RTP: 97.00%
• Volatility: high
• Progressive bonus multiplier: up to x512
• Maximum win: x10,000

The high-volatility designation is relevant before choosing a stake. A large advertised ceiling leaves no assurance of a large payment in a given session, and the long-run RTP does not set a schedule for bonuses. The slot is most interesting as a feature-led game for readers who already enjoy expanding-symbol rounds.

Books, expanding symbols and retriggers

A Book can substitute in winning combinations and also acts as a scatter. Three or more Books trigger ten free spins. Before the round, a random non-scatter symbol becomes the Golden Expanding symbol. Its identity matters because the feature revolves around collecting enough examples of that selected symbol.

Depending on the selected symbol, two or three Golden symbols are required for the described expansion. They cover their reels and create payments on all ten paylines regardless of position. The important distinction is between an ordinary aligned combination and the feature's expanding-symbol payment: the bonus has its own way of using the chosen symbol.

Three or more Books inside free spins retrigger the feature with ten additional spins. A retrigger extends the opportunity to use the selected symbol, rather than guaranteeing that it will appear in a paying arrangement. Watch the symbol shown above the reels as well as the remaining-spin counter.

Super Free Spins starts with three or more Golden Scatters and adds a progressive multiplier. It begins at x1. A spin without a win doubles it; a winning spin uses the current multiplier and then resets its value. The multiplier stops growing at x512.

This creates a clear risk-and-release rhythm. Losing bonus spins can build a larger multiplier, but they are still spins without a payout. A high counter is only one ingredient: the following win must occur for that accumulated value to be applied.

Paid features and our editorial verdict

The Buy menu offers direct entry to Free Spins or Super Free Spins. Prices are shown in the game's purchase pop-up and adjust to the chosen bet. The next spin after purchase activates the selected feature. Because the official profile does not give a fixed price table in its text, we do not assign an unconfirmed universal purchase multiplier.

Chance x2 is another option. It raises the bet to double the probability of triggering free spins and is disabled while Buy Bonus is active. A doubled chance describes a relative change, not a promise that the feature arrives in two spins or within any particular budget.

The official demo works alongside support for desktop, smartphones and tablets. Use the demo to distinguish the regular expanding-symbol round from the progressive version: one is about the selected symbol, while the other also makes the sequence of losing and winning spins visible through its counter.

Our verdict: Book of Hidden Tombs has a meaningful Super Free Spins twist and a straightforward base-game identity. The most suitable audience is comfortable with high volatility and enjoys following a bonus state rather than expecting frequent large results. Set a session limit before any purchase and treat the price of the entire feature as money at risk.

Source: BGaming's official Book of Hidden Tombs page, with its linked official screenshot and promo pack. Checked October 15, 2026.