Book of Ultimate Infinity Slot Review

Try and unlock the mysteries of ancient Egypt in the Book of Ultimate Infinity slot. This ancient adventure uses Infinity Reels where landing 3 identical symbols or wilds on reels 1, 2 and 3 adds an extra reel. More and more reels are added if you land more matching symbols or wilds. Each added reel brings expanding multipliers into play too. If the reels expand to reach the gold book symbol, you’ll trigger the Free Spins feature and with it, 10 free spins. During the free spins, 1 symbol is picked to be a special expanding symbol. Found out more about this unusual slot in our in-depth Book of Ultimate Infinity review.

Where to Play Book of Ultimate Infinity Slot

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Book of Ultimate Infinity Slot RTP, Details & Wager Limits

In the Book of Ultimate Infinity slot, each spin starts on a 3 reel, 4 row machine. If you land 3 matching symbols or wilds on reels 1, 2 and 3, an expansion occurs and an extra reel is added. The process is repeated if further matching symbols or wilds appear.

This is known as the Infinity Reels mechanic which was developed by ReelPlay. When you have 5 or more matching symbols across successive reels, you’ll create a winning combination which pays the symbol value. Extra reels adds to the payout amount.

For your reference, other games using this mechanic include El Dorado Infinity Reels and Odin Infinity Reels Megaways (both by ReelPlay).

Stake levels in Book of Ultimate Infinity range from 20p to £50 per spin. Click on the coins below the spin button then use the + and – buttons to adjust. Autoplay is available if required. You can set between 5 and 100 autospins as well as win and loss stop limits. Just click on the arrows tab below the spin but to get this going. Click on the lightning bolt for turbo mode.

The Book of Ultimate Infinity RTP is 96.5% which is about average. Medium to high variance, the max win is capped at £250,000 per spin.

Theme – Audio & Design Features – head to ancient Egypt  


With an ancient Egyptian theme, there’s a high-class feel to the sound and visuals in the Book of Ultimate Infinity slot. The reels are set against a rather lovely backdrop of turquoise skies, wispy white clouds, pyramids, palm trees and an oasis. Visually, it’s super sharp.

Complementing the impressive visuals is a sweeping orchestral backing track which has just the right amount of Arabia and delivers plenty of atmosphere. We’ve sometimes been a bit underwhelmed by the design of slots from WMS but they’ve come up trumps with Book of Ultimate Infinity.

On the reels, you’ll find A to royals, a dagger, an ankh cross, a Pharaoh queen and a bird god statue. The ornate burial mask is the most rewarding symbol. This pays 0.25 x stake per symbol. That doesn’t sound like much but as you’ll discover below, winning combinations bring expanding multipliers into the mix. There’s also a wild that substitutes for all the standard symbols when it forms part of a winning combination.

You can try and land some of the pharaoh’s riches while playing on your smartphone. The Infinity Reels mechanic is well-suited to play on a smaller screen device. The super sharp visuals also work well here. Put that together with the unusual gameplay and the Book of Ultimate Infinity mobile slot is a playable one.

Book of Ultimate Infinity Bonus Features

The Infinity Reels are central to the bonus action in this Egyptian treasure hunt. If they reach far enough, you’ll trigger a free spins round, complete with a special expanding symbol.

Symbol Multiplier feature


When you land a winning combination, extra reels are added with the Infinity Reels mechanic. The first extra reel pays 2x the symbol amount with each subsequent reels increasing that multiplier by 1. So 5 reels = 3x, 6 reels = 4x and so on. The Infinity Reels expansions keep on coming as long as a new matching symbol or wild lands. This is known as the Symbol Multiplier feature.

Free Spins feature


The gold book is the game’s bonus symbol. On each spin, this will appear on a randomly chosen position between reels 6 and 15. If the Infinity Reels expand far enough to reach the gold book, you’ll trigger the Free Spins feature. You’ll be told how close you are to reaching the gold book on each spin.

Once triggered, you’ll receive 10 free spins. Before the round starts, 1 symbol is picked at random to become the special expanding symbol for the duration of the free spins. If you land an expanding symbol on the rightmost reel, an extra reel is added whether or not the original winning combination is improved.

When the special expanding symbols lands on 2 or more reels, it fills out and pays once per symbol. They don’t have to be on consecutive reels. If you reach the gold book during the feature, you’ll get a retrigger and another round of 10 free spins. The number of free spins is, like the mechanic, infinite.

Book of Ultimate Infinity Review Summary – innovative twist to special expanding symbols

There are few more popular genres in the slot world than ancient Egypt. WMS has taken that familiar theme and created something different thanks to the Infinity Reels game mechanic. If you’ve not played a slot using these expanding reels, I recommend you try this game out in demo mode first until you get your eye in (scroll to the top of the review).

The bigger wins will come in the Free Spins feature, especially if you land a high value expanding symbol. What you make of this slot will largely be down to your thoughts of the Infinity Reels.

It combines special expanding symbols in the free spins from classic slots like Book of Dead and adds this crazy mechanic to offer something new and unique. Overall, the Book of Ultimate Infinity slot will appeal to many.

Book of Ultimate Infinity FAQs

What is the Book of Ultimate Infinity RTP?

The Book of Ultimate Infinity return to player rate is 96.5%. Higher than most slots, the variance is medium to high with the bigger wins coming from the symbol multipliers and free spins.

What is the Book of Ultimate Infinity max win?

The most you can win playing this ancient Egyptian game is £250,000 per spin. With infinite reels and unlimited wins in theory, the max win is capped at this number on each spin.

What are Infinity Reels?

Infinity Reels is a mechanic developed by ReelPlay. Each spin starts with 3 reels. Land a matching symbol or wild on all 3 reels and an extra reel is added. These extra reels keep on coming as long as a new matching symbol or wild appears. Extra reels also boost the value of your payout with expanding multipliers.

Is there a Book of Ultimate Infinity free spins feature?

Yes, trigger the Free Spins feature by reaching the reel with the golden book. You’ll then get 10 free spins. A special expanding symbol is active here too. You can also benefit from increasing multipliers and unlimited more free spins.

Book of Ultimate Infinity Slot Information

  • Game:
    Book of Ultimate Infinity
  • Provider:
  • Type:
    Video Slot
  • Reels:
  • Paylines:
  • Stakes Range:
    20p to £50
  • Bonus Features:
    Yes (2)
  • Free Spins/Multiplier :
  • RTP %:
  • Max WIn:
Review by Chris Taylor

Review by Chris Taylor

Chris is a slots expert that has reviewed and played over 4,000 online slots. Having being in the iGaming industry for over 16 years, he knows how slots work, how bonus features are triggered and how the RTP and variance affect the gameplay.