Book of 99

Book of 99

Head to the next chapter in our online slot game, Book of 99.

You could unlock a re-triggering Free Spins bonus if 99 Book symbols are displayed on the reels.

Plus, if the Warrior feature is activated then it will expand across the reels, which could lead to a maximum win of 5,000x your bet.

Open the book.

    Book of 99 Slot Game Overview

    The bet sizes available in Book of 99 range from 10p to £50.

    Betting in this game is fixed at 10 paylines.


    A collection meter is active in this game, beginning at 0 and going up to 99.

    The collection meter is boosted by 1 for each Wild symbol that is displayed in the main game.

    It is possible to trigger Free Spins in two ways; either land at least three Wild symbols anywhere on the reels on a single spin, or accumulate enough Wild symbols to complete the collection meter.

    When activating Free Spins through collection, the bet size used is the weighted average of the bet sizes used when each Wild was collected.

    If you activate Free Spins by landing a minimum of three Wilds on the reels, your free spins are playing with the same bet size as the triggering spin.

    The average bet size is required to be an integer multiple of the minimum bet. If this is not the case, it is rounded according to the rules of stochastic rounding (e.g. if the average becomes 1.2 times the minimum bet, with a 20% probability it will be rounded to 2x the minimum bet and with 80% probability it will be rounded to 1 times the minimum bet).

    Once 99 Wild symbols have been collected and Free Spins is unlocked, the collection meter is reset to 0.

    Should you collect a greater number of Wilds than 99, and Free Spins has been triggered, the collection meter will be reset to include the remaining Wild symbols (e.g. if collecting 101 Wild symbols, the collection meter will be reset to 2).

    If you simultaneously land three or more Wild symbols and complete the collection meter on the same spin, you will play the Wild triggered Free Spins first, followed by the collection triggered Free Spins.

    Free Spins

    When Free Spins is initiated, you receive 10 free spins.

    For the duration of this bonus, the special symbol will be one of the nine randomly chosen regular symbols.

    Any normal wins are paid out first on every spin. 

    If enough of the special symbols are in play (two for high paying symbols and three for low paying symbols), they expand to cover the whole reel and pay out for each of 10 lines, regardless of their horizontal position. This is done according to the number of symbols and the corresponding pay table value. 

    Note that any existing Wild symbols will not be included in the expanded special symbol payout.

    To re-trigger Free Spins, land at least three Wilds anywhere on the reels during a spin in this bonus, and you receive a further 10 spins.

    Return to Player

    Return To Player (RTP): 99.00%.

    The expected return is the amount we pay out to players relative to the amount of wagering on the game.

    For example, if we take £100 of wagers we will, on average, pay out £99.00.

    More Slots you might like

    Secrets of the Phoenix

    Double Bubble Jackpot


    Rainbow Riches