Book of Unseen Slot Review

Several bonus features in the game make it a worthwhile experience. The main ones include free spins with expanding symbols, the ability to trigger the bonus with the Book symbol, and of course, the Bonus Buy feature to buy your way into free spins. The game also has guaranteed expansions in free spins and a variety of rewarding mechanics, with the potential for some big wins during the bonus rounds.

Free Spins Bonus

Land three or more Book of Unseen symbols (the scatter) on the reels to trigger the free spins round. The number of free spins you receive depends on how many scatters appear:

• 3 scatters = 4 guaranteed expanding symbols
• 4 scatters = 6 guaranteed expanding symbols
• 5 scatters = 10 guaranteed expanding symbols

During this bonus, one regular symbol is randomly chosen to become an expanding symbol. These expanding symbols cover the entire reel when they land. The free spins round can be retriggered by landing more scatters, which adds even more expanding symbols, up to a maximum of 99 expansions.

A word of caution—it is not really easy to get big wins out of this.

Bonus Buy Feature

The Bonus Buy Feature allows you to skip the wait and buy direct access to the Free Spins Bonus. For 100x your bet, you can instantly trigger the bonus round with a random number of expanding symbols (3, 4, or 5 book symbols). This feature is good for you if you want to jump straight into the action without waiting for the Scatter symbols to appear naturally. The Bonus Buy feature guarantees a chance at big wins, but be careful in using it. The Bonus Buy feature in slots is a double-edged sword and does harm more often than good.

Expanding Symbols Mechanic

During the Free Spins Bonus, the expanding symbol is chosen randomly at the beginning. It then expands whenever it appears on the reels. This expansion helps form multiple winning combinations, even across paylines. It can help create significant payout opportunities. At its core, this mechanic ensures that each free spin has the potential for big wins. The expanding symbols can trigger large payouts if you are lucky enough to land them in the right positions.

Book of Unseen has an interesting, occult-themed adventure that successfully delivers on several fronts. The engaging theme, solid RTP, and potential for big wins with the expanding symbols in the Free Spins Bonus are highlights. However, while the game stays true to the “Book of” theme vibe, it does not quite innovate enough to stand out among its competitors. The lack of more interactive or unique bonus rounds makes it feel somewhat restrained, even though the core gameplay is strong. The Bonus Buy feature gives you the option to skip to the action, which is useful but could potentially harm your bankroll. Still, IGT has delivered a well-rounded slot with a nice blend of excitement and potential payouts, earning a solid rating. While it may not dethrone the giants of the genre, Book of Unseen still offers a fun, mystical experience for fans of detective and occult-themed slots.

Rating: 8 (Very Good)

The game keeps the “Book of” vibe intact. It has all the ingredients that are needed to beat some other Books, in my opinion, but dethroning the long-standing champions seems unlikely not because of the comparative lack of popularity owing to its recent debut, but because of the lack of interesting bonus games. In my opinion, IGT missed an opportunity here to deliver some interesting gimmicks and interactive bonus rounds. They certainly wanted it to compete with the fancier slots, as evidenced by the intro and all the work they have done on the theme, but they stopped short, it feels. That being said, the core gameplay is very good (hence, the rating). And my hats off to IGT for not offering RTP ranges dipping into the dark sub-80% realm.