Holy Diver slot review

Holy Diver slot: key facts

Holy Diver comes from Big Time Gaming, the Sydney studio behind the Megaways mechanic. It’s one of the studio’s more unusual designs because the bonus isn’t triggered by scatters at all. Instead, you build towards it with gems and then decide what to do with a full meter.

Big Time Gaming was founded in 2011, is led by chief executive Nik Robinson and became part of Evolution after a deal announced in April 2021. Its other well-known games include Bonanza, Extra Chilli and White Rabbit.

How the features work in Holy Diver

Holy Diver has three layers: wild features in the base game, a gem meter that builds between spins and a free spins round that gets stronger at higher levels.

The knight and the chests

During the base game, a knight opens chests that award wild features. The published features include stacked wild reels carrying multipliers, fireballs that turn nearby symbols wild, and gems that turn wild. Each one adds wilds to the current spin, which is what connects symbols across the six reels.

The gem meter

Gems also fill a meter with four slots. When the meter is full, the game stops to offer you a choice: level up, or start free spins now. This replaces the usual scatter trigger, so you can see your progress towards the bonus rather than waiting for a random landing.

Free spins

Free spins begin with 10 games. During the round, the knight collects diamonds, which award extra spins and also increase the number of ways. Gems act as wilds in the bonus and carry multipliers at higher levels. That’s the reason levelling up can matter: the round you eventually play is shaped by the level you reached.

The casinos.com Holy Diver page (opens in a new tab) gives a similar summary, and the game’s own help screen has the exact level details for the version in your app.

Level up or free spins? The Holy Diver gem meter choice

The decision at a full meter is the heart of the Holy Diver slot. Here’s the order things happen in:

1. Gems land during base-game spins and fill the four-slot meter.
2. When all four slots are full, the game offers two options.
3. Choose level up to move to the next level and start filling the meter again.
4. Or choose free spins to start the bonus at your current level.
5. In free spins, 10 games are awarded to start, and diamonds the knight collects add spins and ways.

Higher levels make the free spins stronger, because gems carry multipliers. The cost is time: levelling up means more paid spins before you see a bonus. The published RTP range, 96.39% to 96.54%, varies by level, and so does the volatility, so the game is designed to change character as you progress.

No choice changes the house edge in your favour beyond the published range. The difference between the lowest and highest level RTP is 0.15 percentage points, about 15p per £100 staked on average. Decide based on how long you want the session to be, not on any idea that a level is ’due’ to pay.

Megaways maths: how Holy Diver reaches 117,649 ways

In a Megaways game, the number of ways on each spin is the number of symbols shown on each reel multiplied together. With six reels, the top count needs seven symbols on every reel.

The last two rows are worked examples of the multiplication, not published Holy Diver outcomes. The number of ways changes how a spin looks and how many routes exist, but the RTP already accounts for all of it. The mechanic is covered in more depth in Megaways slots on mobile.

What the Holy Diver slot costs to play

With RTP between 96.39% and 96.54%, the house edge is 3.46% to 3.61%. Expected loss is stake x house edge, so the table shows a range rather than one number.

Because the bonus is built through the gem meter rather than a single lucky landing, a very small number of spins is unlikely to show you much of the game. At £1 a spin, a £20 budget gives 20 spins; at 10p, it gives 200. The top win of 23,306x would be £2,330.60 at 10p and £116,530 at the £5 cap, but it’s a ceiling the maths allows, not an expectation.

To keep spending fixed, set a limit before you start. Setting deposit limits in a casino app walks through it step by step.

Playing Holy Diver on a phone

Holy Diver opens in casino apps and mobile sites on iPhone and Android from the casino’s game lobby, with no separate download. A six-reel grid with up to seven symbols per reel means up to 42 positions on screen, so a larger phone makes the knight’s features easier to follow.

Whether the game offers portrait as well as landscape depends on the version the casino runs, so rotate your phone to check. If you’re choosing an app partly for Megaways games, Coral’s App Store listing says its casino app includes Megaways slots; our list of best Megaways slot apps covers other options. Search the lobby for Holy Diver itself, because a general Megaways section doesn’t mean every title is there.

UK rules that shape Holy Diver

Holy Diver on a UK-licensed app follows the Gambling Commission’s online slot rules, most of which came in with its 2021 package of game design changes (opens in a new tab).

Since a Gambling Commission warning in January 2020, feature buy-ins are not offered to British players, as the Commission’s games warning (opens in a new tab) explains. In Holy Diver, the gem meter is the only way to the bonus. Our page on slot stake limits has more on the caps.

Holy Diver vs other Big Time Gaming slots

Big Time Gaming has several Megaways and grid games on our site. Here’s how they line up on published figures.

Bonanza Megaways is one of the studio’s best-known Megaways titles, and White Rabbit Megaways has the highest RTP in the table. Extra Chilli Megaways is the closest on top win. Our answer to which casino apps have Megaways slots explains how to find them.

Holy Diver slot review: who it suits

Holy Diver suits players who like a sense of progress and a real decision, rather than waiting for scatters. It asks for patience, because the strongest free spins come after levelling up. It’s less suited to very short sessions.

There’s more to compare in our mobile slot reviews.

Where to play Holy Diver on UK casino apps

Search an app’s lobby for Holy Diver before you sign up; we can’t confirm it at any particular partner. The offers below are welcome offers on slots chosen by each casino, which may not include Holy Diver. They’re for new customers aged 18+, and terms apply.

• PlayOJO: new UK customers (excluding Northern Ireland) who make a first deposit of at least £10 get 80 free spins on Big Bass Bonanza at 10p each. There’s no wagering, so winnings are cash. It’s only available through the designated offer link and can’t be combined with other offers.
• Coral: make a qualifying deposit and bet £10+ on slots to get 100 free spins at 10p on selected games, with no wagering on winnings. Accept them within 48 hours; they’re valid for 7 days. Runs 1 October 2026 to 1 February 2027. Neteller, PayPal, Paysafe, Skrill, prepaid cards and certain debit cards don’t qualify.
• Ladbrokes: deposit and spend £10 on slots for 50 free spins a day across your first 10 days, up to 500, each worth 10p on selected games, with no wagering. Claim before 23:59 each day; spins last 7 days. Prepaid card, PayPal, Paysafe, Neteller, Skrill and Moneybookers deposits are excluded.

As Coral and Ladbrokes are both run by LC International Limited (Entain), you may not be able to hold new accounts at both. Bonus spins are a slot offer and don’t apply to table or live games.

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.