Relax Gaming’s Book of 99 pairs a classic expanding-symbol Free Spins round with a second way in: every Book Wild landed in the base game fills a meter that awards 10 Free Spins at 99. This card covers the rules, the paytable and the listed 99.00% RTP.
Demo availability may vary by location. You must meet the legal age in your jurisdiction; the free-play button does not record acceptance.
Book of 99 is a video slot from Relax Gaming, released on 4 May 2021. Greek mythology frames four character portraits and five card symbols on a 5×3 grid with 10 fixed paylines, and the studio’s product page advertises up to 5,000× the stake for the expanding symbol. Listed RTP is 99.00%.
This card follows Relax Gaming’s product page and release announcement, the game-design sheet, operator rules and the attached demo frames. It is not a report of played cash sessions.
For adults of legal gambling age in their location. Set a budget you can afford to lose.
Read full reviewListed RTP is 99.00% in Relax Gaming’s game-design sheet and on its product page. The sheet puts 50.01% in the base game, 23.42% in naturally triggered Free Spins and 25.58% in collection-triggered Free Spins.
All 10 fixed paylines are active on every spin, and wins are read from the leftmost reel on consecutive positions, with only the best combination paid per line. The Book symbol is both Wild and Scatter: it completes line wins and, three at a time, opens the bonus. Premium characters can pay from two matching symbols, the card ranks need three.
Relax Gaming lists RTP 99.00% and rates volatility 5 out of 5. A large share of that return sits in the two Free Spins routes, so ordinary spins can stay quiet.
Book of 99 suits readers who like classic paylines, Greek mythology artwork and a book-style bonus that can be reached either by a direct trigger or by collected Wilds, at a listed RTP of 99.00%. It is less suited to anyone who wants a changing grid, cascades, several different bonus modes or a feature buy.
Three or more Book Wilds anywhere in one base-game spin start 10 Free Spins at the stake of the triggering spin. They do not need to sit on a payline or in a set order, and they still help complete ordinary line wins.
A separate meter starts at 0 and advances one step for every Wild that appears in the base game. At 99 it awards 10 Free Spins, then resets to 0, and surplus Wilds carry over: 101 Wilds from an empty meter award the feature and leave the meter at 2. The bonus is played at the weighted average of the stakes used when each collected Wild landed, with stochastic rounding if that average is not a whole multiple of the minimum bet. If both triggers happen together, the Wild-triggered Free Spins are played first, then the collection-triggered ones.
At the start of the feature one of the nine regular paying symbols is chosen at random as the expanding symbol and stays selected. Each spin pays normal line wins first. Then, if two of a premium symbol or three of a low symbol have landed, the symbol expands over its whole reel and pays on all 10 lines, with no need for a left-to-right chain. Wilds are not counted for this award, and the Book Wild does not substitute for the expanding symbol.
Three or more Book Wilds anywhere during a Free Spin add another 10 Free Spins without changing the selected symbol.
Set a money limit and a time limit before spinning. The 99 meter is a counter, not a countdown, so the next Wild or the completion of the meter cannot be predicted. Do not raise the stake just to move the meter faster, because earlier stakes feed the average used for the collection bonus.
Keep the stake steady
Changing bets while the meter fills changes the weighted average that sets the collection Free Spins stake.
Treat the meter as a counter
A high count does not make the next Wild or the next bonus more likely.
Set the pace
Where Turbo Spin or Autoplay are offered, fix a spin count and a time limit before using them.
Symbols follow the attached set for Book of 99: the Book Wild, four character portraits and the card ranks A to 10. x5, x4, x3 and x2 are matching symbols on adjacent reels from the left. Values are multiples of the total bet, converted from the in-game paytable shown at a 2.00 bet.
A red leather book with a golden lightning bolt on a teal tile. It substitutes for regular symbols, but not for the expanding symbol in Free Spins. Three or more anywhere in one spin start 10 Free Spins, and each Book Wild in the base game adds a step to the 99 meter. It has no payout of its own.
Relax Gaming’s game-design sheet and product page list Book of 99 at a theoretical RTP of 99.00%. The sheet splits it into 50.01% from the base game, 23.42% from naturally triggered Free Spins and 25.58% from collection-triggered Free Spins; the rounded parts add up to 99.01%, so the gap is rounding. The sheet rates volatility 5 out of 5, and the product page advertises up to 5,000× the bet for the expanding symbol. RTP is a long-run theoretical return, not a forecast for one session. The 5,000× figure is a multiple of the bet, not a profit and not a stated cap on a whole round.
Relax Gaming
High
5,000×
A long quiet stretch does not make the next Wild or the 99 meter any more due.
Confirm RTP, the meter count and your current stake before spinning.
Listed RTP is 99.00%, but a large share is tied to the two Free Spins routes, so base-game spins can stay quiet.
Screenshots cover the intro screen, the paytable, the Free Spins rules, the base game with the 99 meter and a line win at a 2.00 bet.
Mobile frames mirror the portrait intro, two base-game views, the paytable for the card ranks and the Collection rules page.
Grid: 5×3 reels
Win system: 10 paylines
RTP: 99.00%
Bonus: 10 Free Spins
Other Relax Gaming and book-style slots also sell expanding-symbol Free Spins, but Book of 99 adds a second way in: a meter that counts every base-game Book Wild up to 99 and pays 10 Free Spins at the weighted average stake. Compare the listed 99.00% RTP, the high volatility and both trigger rules before treating another book slot as interchangeable.
| Game | Return / max win | Volatility | Bonus fit | Watch out for |
|---|---|---|---|---|
| Book of 99 | 99.00% / 5,000× | High | 99-Wild collection meter, two routes into 10 Free Spins, random expanding symbol, repeatable retriggers | Shared studio branding does not copy this card’s RTP, trigger rules or stake averaging. |
| Book of Dead | 84.18%–96.21% / 5,000× | Very High | Ten Free Spins select one ordinary symbol that can expand under a separate award rule; qualifying Scatters can add another ten spins. | Regular awards are expressed per line, while Scatter awards use total bet. The two units must not be combined without conversion. |
| Legacy of Dead | 84.55%–96.58% / 250000 coins | High | Eight Free Spins select one expanding symbol; qualifying Tomb Scatters add eight spins and another selected symbol. | Shared Egyptian art does not transfer Book of Dead’s ten-spin start or a single RTP figure across titles. |
When comparing, ask whether the bonus has a second trigger and which stake it is played at.
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Publication status: Document-based review against Relax Gaming’s product page and release announcement, the game-design sheet, operator rules and the attached demo frames; no cash session is represented.
Rules. Checked the 10 fixed paylines, the Book Wild and Scatter role, both Free Spins triggers, their order, the stake averaging, the expanding symbol and the retriggers against the rules pages.
Paytable. Compared the nine regular symbols with the in-game paytable shown at a 2.00 bet and converted the figures to total-bet multiples; a line of four 10s paying 5.00 confirmed the conversion.
RTP. The game-design sheet and product page print 99.00%, with 50.01%, 23.42% and 25.58% as the three contributions to that total.
Maximum win. Kept the product page’s 5,000× feature headline apart from a round cap; the design sheet and later secondary listings do not give one consistent limit.
Player reviews
Player opinions about gameplay, pacing and usability. Ratings are unweighted and moderated separately from session data.
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Relax Gaming lists 99.00%. The design sheet splits it into 50.01% from the base game, 23.42% from natural Free Spins and 25.58% from collection Free Spins. RTP is a long-run theoretical return, not the chance of winning one spin.
All 10 fixed paylines are active. Matching symbols pay from the leftmost reel on consecutive positions, and only the highest combination on each line is paid. Premium characters can pay from two symbols, the card ranks need three.
Three or more Book Wilds anywhere in one base-game spin start 10 Free Spins at that spin’s stake. A second route is the 99-Wild meter, which also awards 10 Free Spins.
It starts at 0 and gains one step for every Wild in the base game. At 99 it awards 10 Free Spins and resets, and surplus Wilds carry over to the next count.
The weighted average of the bets used when each collected Wild landed, not just the last spin. If it is not a whole multiple of the minimum bet, the game rounds it by chance.
The Wild-triggered Free Spins are played first, followed by the collection-triggered ones. They are not merged into one larger package.
One of the nine regular symbols is chosen at random for the feature. After normal line wins, two premium or three low copies make it expand over its reel and pay on all 10 lines, with no left-to-right chain needed.
Yes. Three or more Book Wilds anywhere during a Free Spin award another 10 Free Spins, and the selected expanding symbol stays the same.
Relax Gaming’s product page advertises up to 5,000× the bet for the expanding symbol. The figure is a multiple of the bet, not a profit, and not a stated cap on a whole round.
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