TNT Tumble slot review

TNT Tumble slot overview

TNT Tumble is a cluster pays slot from Relax Gaming. Instead of paylines, it pays for groups of matching symbols, and each win clears space for new symbols to fall in. The hook is a grid that physically grows during a spin as you break through stone underneath it.

Relax Gaming was founded in 2010, started out in Tallinn, Estonia, and is now headquartered in Malta. It has made its own slots since 2018 and holds a Gambling Commission licence under account 37462.

How the features work in TNT Tumble

Everything in TNT Tumble happens inside one paid spin, which can run through several stages before it ends. A typical winning sequence looks like this:

1. You spin and the 5x4 grid fills with symbols.
2. A cluster of 3 or more matching symbols pays and is removed from the grid.
3. New symbols drop in to fill the gaps, which is the tumble.
4. Wins also break stone blocks beneath the grid, and each break opens more space, up to 5x7.
5. A TNT symbol can land and blast out a whole row, making room for more symbols.
6. Drill wilds can appear as part of wins and move down the reels.
7. The sequence repeats until no new win forms, and the spin ends.

The stone blocks are the link to the bonus. If one spin’s chain of wins clears all of the dark blocks, it triggers six free spins. Before they start, you choose between extra spins, multipliers or a combination of the two. The OLBG summary of TNT Tumble (opens in a new tab) describes the same mechanics, and the help screen in your app has the exact rules for the version you load.

How cluster wins are counted in the TNT Tumble slot

In a cluster pays game, matching symbols pay when they sit in a connected group, not when they line up from left to right. TNT Tumble pays for groups of three or more, and the paytable shows how much each symbol pays for each cluster size.

As the grid grows from 20 to 35 positions, there’s more room for larger clusters to form. That’s why the expansion matters: it doesn’t change the long-run return, but it changes what a single spin can produce. For a wider look at reel formats and chained wins, see our guide to slots on mobile.

Cluster rules differ between games, including what counts as touching. Check the game’s help screen for the exact definition before you play.

TNT Tumble free spins: extra spins, multipliers or a mix

The choice at the start of the bonus is the one decision you make that changes how the round plays. The game’s help screen lists the exact options, but the trade-off works like this:

None of these options gives you better long-run value than the others: the RTP is built on the whole game, including the bonus. Picking multipliers simply makes the round swingier, and picking spins makes it steadier. Choose the one you’ll enjoy more, not the one you think is due to pay.

TNT Tumble RTP and what a session costs

At a 96.11% RTP, the house edge is 3.89%. Expected loss is stake multiplied by house edge, so the average cost is about 3.89p for every £1 you stake. Here’s what that means for a £20 budget and for an example 500 spins.

Medium–high volatility means results bunch together: a run of blanks, then a chain that clears a lot of stone. At £1 a spin, 20 spins is a short session, and the bonus may not appear. At 10p, the same £20 gives ten times as many spins. Either way, the house edge means losses are the likely outcome over time, a point Wizard of Odds explains in its slots guide (opens in a new tab).

Our guide to checking a game’s RTP in an app shows where to confirm the figure before you play, because operators can choose game versions.

TNT Tumble on mobile: the growing grid on a small screen

TNT Tumble opens inside casino apps and mobile sites on iPhone and Android, from the casino’s game lobby. The interesting phone-specific point is the grid: it starts at 20 positions and can reach 35, so the screen gets busier as a spin goes on.

1. Open a UK-licensed casino app and log in; age and identity checks must be complete before you play.
2. Search the lobby for TNT Tumble. If it’s not there, that casino doesn’t offer it.
3. Check the help screen for the RTP and the free spins options.
4. Set your stake within the UK cap for your age.
5. Tap to spin, and let each tumble sequence finish before the next spin.
6. Keep an eye on the net spend and time display that UK games must show.

Tumbling games can run several animations in one spin, so sessions can feel longer on screen than on a simple three-row slot. Our guide to casino apps and battery life explains what affects it, and portrait games covers games built for one-handed play.

UK rules for the TNT Tumble slot

TNT Tumble plays under the Gambling Commission’s online slot rules on every UK-licensed app. The Commission’s responsible product design standard (opens in a new tab) covers game speed and presentation.

• Each paid spin must take at least 2.5 seconds, and there’s no turbo or slam-stop to skip the animation (since 31 October 2021).
• Autoplay is banned, so each spin needs its own tap.
• A chain of tumbles that returns your stake or less can’t be celebrated as a win.
• Your net spend and time played are shown in real time (since 17 January 2025).
• The maximum stake is £5 a spin at 25 and over, and £2 at 18 to 24. See slot stake limits.
• Since a Gambling Commission warning in January 2020, feature buy-ins are not offered to British players, so free spins only start by clearing the stone blocks.

Our page on UK game design rules has the full timeline.

TNT Tumble vs similar slots

If you like TNT Tumble, these are the closest comparisons on our site: other Relax Gaming games and other grid-based slots where wins clear space.

Temple Tumble Megaways is the closest relative from the same studio. Reactoonz and Jammin’ Jars are well-known grid slots with higher volatility. For Relax’s best-known series, see Money Train.

TNT Tumble slot review verdict

TNT Tumble suits players who like watching a spin develop, with tumbles, row-clearing TNT and a grid that grows underneath. Its bonus choice adds a small but genuine decision. The downsides are a top win that isn’t published in the specifications we rely on and a busy screen on smaller phones.

See more reviews in our mobile slots hub, or the apps we rate in best slot apps UK.

Casino apps for playing TNT Tumble

We can’t confirm that TNT Tumble is in a particular partner’s lobby, so search before you sign up. The welcome offers below run on slots each casino names in its terms, not necessarily this one. They’re for new customers aged 18+, and terms apply.

• PlayOJO: 80 free spins on Big Bass Bonanza, 10p each, for new UK customers (not Northern Ireland) who make a first deposit of £10 or more. No wagering, so any winnings are paid as cash. Available only via the designated offer link; not combinable with other offers.
• Coral: after a qualifying deposit, bet £10+ on slots and get 100 free spins at 10p on selected games. You have 48 hours to accept and 7 days to use them, and winnings carry no wagering. Offer period 1 October 2026 to 1 February 2027; Neteller, PayPal, Paysafe, Skrill, prepaid cards and certain debit cards are excluded.
• Ladbrokes: deposit and spend £10 on slots for 50 free spins a day for 10 days, up to 500, worth 10p each on selected games. No wagering; claim before 23:59 each day, and use within 7 days. Prepaid cards, PayPal, Paysafe, Neteller, Skrill and Moneybookers don’t qualify.

Coral and Ladbrokes are both run by LC International Limited (Entain), so you might not be able to open new accounts at both. For more choice, see casino apps with free spins.

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.