Book of 99 Featured Image

Book of 99 Offering 99% RTP

Relax Gaming have an impressive catalogue of slots available, including Money Train 2, Iron Bank, and Mega Masks. Some of the games on offer, like Money Train 2, are incredibly volatile. These slots prove on the dangerous side for play on a higher stake. This year, in May 2021, Relax are offering us a new release – Book of 99 (Read the full Slot Review here). Book of 99 offers the highest RTP of any slot we've seen so far, a whopping 99%. 

Book of 99
Book of 99, by Relax Gaming

“The Highest”

This seems like an intelligent move, since players love to talk about slots that offer “the highest” of anything. The highest possible max win, the highest possible volatility, or the highest amount of features (Blueprint hold that crown, though). When Nolimit City's San Quentin was released at the beginning of 2021, it sent the slot sector into a frenzy at the thought of offering 150,000x bet. Games already existed offering over 100,000x bet, with Lil' Devil being the prominent example. It didn't matter, though, how much higher of a win San Quentin offered, it just mattered that it was the highest.

The same pattern will likely follow suit with Book of 99, where players will be inclined to play the game based upon the high RTP. However, it will be interesting to see how this RTP will look for individual players across the globe. On the one hand, some players do feel that RTP makes a difference, and choose their Casinos and their Slots around this. For other players, they feel the difference just isn't big enough to care on an individual scale.

Book of 99 Win Probabilities
Win Probabilities on Book of 99

The Effect of RTP

Of course, we've spoken of RTP before, including the Short Term Volatility versus the Long Term Predictability. You can read about Different Kinds of Slots here. This is how slots are considered to be volatile. If RTP was set in stone for every set of 100 spins we begin, then volatility wouldn't factor in. This is because we would always receive a 95-97% return, if RTP was on target for every player, every time. Generally, slots play out in a volatile way short term. That said, as time goes on, you should expect to get closer to the target RTP on each game over time.

We still expect to see some players with an RTP of over 200% within a session on Book of 99. Other players may experience incredibly low RTP after an unlucky set of spins. This is a given on any slot. However, we're interested to see a 99% RTP slot, and see if it really does have a noticeable effect on individual, daily play.

Book of 99 Information
Important Information, Such as Hit Rate, on Book of 99

Please remember that, just as mentioned above, you are never guaranteed the RTP advertised in a small amount of spins (e.g. 100). RTP is indeed measured over millions of spins. Do not be tempted to raise your stakes because the RTP is higher. Always gamble within your means.

When the fun stops, stop. Visit for more info.

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