Gigantoonz slot review

What the Gigantoonz slot is

Gigantoonz is a Play'n GO title built around a large square grid rather than reels and lines. Matching symbols that touch each other form groups, and a group of six or more pays. That system is known as cluster pays.

Two things set it apart: oversized symbols that can fill a big chunk of the 64-position board in one go, and a meter that charges as you win.

Gigantoonz RTP: why the version matters

The 96.25% figure is the highest RTP version of Gigantoonz. Play'n GO, like many studios, supplies games at more than one RTP setting, and each casino picks which it uses. That’s why two apps can show different figures for the same slot.

At 96.25%, the long-run house edge is 3.75%, or about £3.75 per £100 staked. A lower version raises that cost. Gambling Commission rules under RTS 3 (opens in a new tab) require game rules and information about the likelihood of winning to be available, so the figure should be in the game’s help screen.

1. Open Gigantoonz in your casino app but don’t place a stake yet.
2. Tap the menu or information icon inside the game window.
3. Scroll the game rules until you find the RTP or theoretical return line.
4. Compare it with 96.25%; if it is lower, you know the app runs a reduced version.

Our guide to finding a game’s RTP in an app has more detail, and the RTP glossary entry explains the term.

How the features work

Clusters and cascades

Any group of six or more identical symbols linked on the grid wins. The winning symbols are then removed, and new ones drop in to fill the gaps. If the new arrangement forms another cluster, that pays too, and the cascade continues until no fresh win appears.

Mega symbols

Oversized symbols can land in sizes from 2×2 all the way up to 7×7. A big block counts as many matching positions at once, so it can create or extend a cluster on its own.

Random wilds

On a spin that produces no win, wild symbols can appear at random. They give an otherwise dead spin another chance to form a cluster.

The Quantumeter and its four modifiers

Winning symbols charge a meter called the Quantumeter. As it fills, it sets off four modifiers in turn: Disintegration, Metamorphosis, Radiation and, last of all, a modifier that brings in a giant wild. The game’s paytable explains exactly what each one does.

Gigantoonz has no free spins round. All of its features, including the meter, play out during normal paid spins.

Gigantoonz without free spins: what it means for you

Many slots keep most of their value in a bonus round. Gigantoonz spreads it across long cascade chains and the meter instead. A spin that starts with a cluster can keep going, charging the meter as it goes, and the biggest results come from those chains.

This also affects free spins offers. Because Gigantoonz has no bonus round of its own, any free spins you get from a casino are simply paid-style spins at a set value on whichever games the offer names.

Gigantoonz on a £20 budget at three stakes

High volatility means results can swing hard. With £20, you get 200 spins at 10p, 40 at 50p or 20 at £1 if nothing comes back. The fewer spins you have, the more likely the session ends before a long cascade chain appears.

The middle column shows that each £20 put through the game costs £0.75 on average whatever the stake. The last column shows why stake size matters: 720 spins, roughly an hour at one spin every five seconds, puts far more money through at £1 than at 10p. Cascades may stretch each spin, so your own count could be lower.

Gigantoonz max win of 4,000×

The ceiling is 4,000× your stake: £400 at 10p, £2,000 at 50p, £4,000 at £1 and £20,000 at the £5 maximum for players aged 25 and over. That’s a lower cap than many newer high-volatility slots, which makes Gigantoonz a little less extreme at the top end.

A ceiling isn’t a likely outcome. Over time, the house edge means you should expect to lose money, and the house edge by game page shows how slots compare with table games.

Playing the Gigantoonz slot on a phone

Play'n GO builds its games in HTML5, so Gigantoonz runs in casino apps on iPhone and Android and in mobile browsers. The developer doesn’t state a fixed orientation for this game, so the layout depends on how your app frames it.

An 8×8 board squeezes 64 symbols onto the screen, which is more than most slots. On a smaller phone, the meter and the stake controls can feel close together, so take a moment to find each before spinning. A tablet gives the grid more room; see phone vs tablet.

For device requirements, read our guides to casino apps on Android phones and casino apps on iPhone.

UK slot rules that apply to Gigantoonz

Stake caps apply to every online slot: £5 a spin if you’re 25 or over, since 9 April 2025, and £2 if you’re 18–24, since 21 May 2025, under the Gambling Commission’s stake-limit guidance (opens in a new tab). Our slot stake limits page explains how a game cycle is defined.

Since 31 October 2021, UK slots have had no autoplay, a minimum of 2.5 seconds per spin, no turbo or slam-stop, and no celebration of returns at or below the stake, as set out in RTS 14 (opens in a new tab). Our explainer on game design rules covers the full list.

Since a Gambling Commission warning in January 2020, feature buy-ins are not offered to British players. Gigantoonz has no bonus round to buy anyway, so that rule changes nothing here.

Play'n GO slots like Gigantoonz

These grid-based Play'n GO games share the cluster or cascade style:

• Reactoonz 2: 7×7 cluster pays, high volatility, 96.2% top version, 5,083× top win.
• Gemix: 7×7 clusters at medium volatility, 96.83% top version.
• Viking Runecraft: 7×7 clusters, high volatility, 96.71% top version, 5,000× cap.
• Moon Princess 100: a 5×5 grid paying three or more in a row or column, up to 15,000×.

For more ideas, see our mobile slot reviews or the guide to slots on mobile.

Gigantoonz review verdict

Gigantoonz suits players who enjoy watching a busy grid react, and who don’t mind that there are no free spins to wait for. The meter gives each session a sense of building towards something. The giant symbols are the draw, but high volatility means many spins will produce little.

Casino apps with welcome offers for Gigantoonz fans

Our partners’ offers aren’t linked to Gigantoonz, and we can’t confirm which of them stocks it, so look in each app’s game lobby. All three are for new customers aged 18+; terms apply.

• PlayOJO app: first deposit of £10 or more brings 80 free spins on Big Bass Bonanza, each worth 10p, with no wagering and cash winnings. Not open to Northern Ireland residents.
• Coral Casino app: after a qualifying deposit, bet £10 on slots for 100 free spins worth 10p on selected games; accept within 48 hours, use within 7 days, no wagering on winnings.
• Ladbrokes Casino app: spend £10 on slots for 50 free spins a day over the first 10 days (500 maximum) at 10p on selected games; claim before 23:59, valid 7 days, no wagering.

PayPal, Skrill, Neteller, Paysafe and prepaid card deposits are excluded at Coral and Ladbrokes. Our free spins casino apps list compares them side by side.

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.