Book of Oz slot review

Book of Oz slot: the quick verdict

This game takes the familiar book formula and adds a Wizard of Oz theme. It's a straightforward game to learn on a small screen: one special symbol, ten lines and a free spins round where the expanding symbols are the whole story.

The credit goes to Triple Edge Studios, one of the studios under Games Global. Games Global was formed in 2022 when it acquired Microgaming's games portfolio, so a 2018 game like this one was around before the Games Global name existed. Browse more titles in our slot reviews hub.

How the features work

The Wizard's Book: wild and scatter in one

The Wizard's Book is the only special symbol you need to watch. As a wild, it stands in for other symbols to complete wins along the 10 paylines; the paytable shows which. As a scatter, it counts wherever it lands on the five reels, without needing to sit on a line.

Free spins with expanding symbols

Land three or more Books and the free spins round begins. During the round, high-paying symbols can expand, which means a single symbol stretches to fill its whole reel. A full reel of a premium symbol lines up across all three rows at once, and that's where the game's biggest wins come from.

That's the core of it. The in-game rules set out how many spins you get and exactly how the expansion is decided, so open the game's information page for those details rather than relying on any summary, including this one.

In-game free spins come from the slot itself. They're separate from casino welcome spins, which have their own terms.

Book of Oz RTP and high volatility, explained

An RTP of 96.31% means that across millions of spins the game is set to return £96.31 for every £100 staked. The other £3.69 is the house edge. It's a long-run average, so a single evening can land well above or below it.

High volatility shapes what an evening feels like. Most of Book of Oz's return is concentrated in the free spins, especially when an expanding symbol pays across several reels. The base game between bonuses tends to be quiet, and a modest budget can run out before the Books appear.

Before you play in any app, check the RTP on the game's help screen. Our guide to RTP on mobile explains why the same game usually shares its maths across app and desktop.

What 5,000x looks like at real stakes

A multiplier is easier to judge in pounds. The top win is 5,000 times your stake, and these are the ceilings at common phone stakes. They're the most a single round can pay, not something to expect.

Wins of this size are very rare on a high-volatility game. Treat the top line as the edge of what's possible, and plan your session around the cost of play instead.

A £20 budget on the Book of Oz slot

Expected cost is stake × house edge × number of spins. With a 3.69% edge, the averages look small, but high volatility means the actual result usually lands well away from the average in either direction.

At £1 a spin, £20 is only 20 spins, which may not be enough to see the free spins even once. At 10p you get ten times as many chances for the Books to land, which is the main reason high-volatility games feel very different at low stakes. Our low stakes casino apps list covers apps where small stakes are easy to set.

Playing the Book of Oz slot on iPhone and Android

The game runs inside casino apps and mobile sites; there's no separate app for the game. A 5x3 layout with 10 lines is about as simple as slots get, which is helpful on a small screen. Orientation support isn't part of the published specification, so it depends on the casino's version.

1. Download a UK-licensed casino app from the App Store or Google Play.
2. Pass the age and ID checks; UK casinos must complete them before you can deposit or play, under rules the Commission announced in February 2019 (opens in a new tab).
3. Set a deposit limit at the prompt that appears before your first deposit.
4. Search for "Book of Oz" in the game lobby.
5. Tap the information icon to read the RTP and the free spins rules.
6. Choose your stake, keeping the £5 or £2 limit in mind, and spin one tap at a time.

Device-specific help is on our Android phones and iPhone pages.

UK rules that shape Book of Oz in apps

The online slot stake limits cap every spin at £5 if you're 25 or over and £2 if you're 18 to 24. GOV.UK's announcement of the £2 limit for under-25s (opens in a new tab) gives the background. The 2021 design rules in the Commission's RTS 14 product design standard (opens in a new tab) removed autoplay, turbo and slam-stop and set a minimum spin time of 2.5 seconds.

Book-style games elsewhere are sometimes sold with a "buy the bonus" button. Since a Gambling Commission warning in January 2020, feature buy-ins are not offered to British players; the Commission's games warning for online operators (opens in a new tab) explains why. In UK apps, the only way into Book of Oz free spins is to land the Books.

You'll also see a running display of your net spend and time played, as the rules require. More detail is on our page about game design rules.

Book of Oz vs other book slots

The book mechanic has many versions. Here's how Book of Oz sits against four we've reviewed, using each game's published top figures.

On paper, Book of Oz and Book of Dead are close. Book of Shadows is the one for players who accept much bigger swings, and Book of Ra Deluxe has the lowest listed RTP of the group.

Where to play Book of Oz with a welcome offer

Availability varies by casino, so search the game lobby in any app before you join. The offers below are spin offers on named or selected slots, not on Book of Oz. Each is 18+ only and has full terms.

With PlayOJO, a first deposit of £10 or more brings new UK customers (not Northern Ireland) 80 free spins on Big Bass Bonanza at 10p a spin, worth £8 in total. There's no wagering, so any winnings are paid as cash, and the offer can't be combined with others.

With Coral Casino, new players who deposit and bet £10 on slots from 1 October 2026 to 1 February 2027 get 100 free spins at 10p on selected games, worth £10 in total. Accept them within 48 hours and use them within 7 days; winnings have no wagering. Deposits by PayPal, Skrill, Neteller, Paysafe, prepaid cards and certain debit cards are excluded.

With Ladbrokes Casino, spending £10 on slots as a new customer earns 50 free spins a day for 10 days, up to 500 at 10p each on selected games, with no wagering. Claim each day's spins before 23:59; they last 7 days. Both Coral and Ladbrokes are run by LC International Limited (register entry (opens in a new tab)), so you may not be able to hold new accounts with both.

18+. Every casino game has a built-in house edge, so over time you should expect to lose what you stake. Set a budget before you play and stop when it’s gone: safer gambling tools and support. Free, confidential help: National Gambling Helpline 0808 8020 133.