Gargantoonz

Gargantoonz is Play'n GO's November 2023 return to Dr Toonz's lab: a 7x7 cluster grid where five or more touching monsters win and cascade away. Winners fill an Experiment Charger that sets off Gamma Ray Burst, Black Hole and Supernova experiments, and passing all three releases Gargantoon wilds that grow from 1x1 to 3x3 with a multiplier of up to x4, toward a 7,000x cap. We gave the Gargantoonz slot demo 100 spins at $1.

What is Gargantoonz?

The grid sits in a dark panel against a purple starfield. To its left a list logs each cluster under the logo; to its right a round charger dial counts symbols, and below it the Gargantoon dozes in a glass tank.

Five two-eyed monsters lead the paytable, a red one with a crown, a pink one, a spiky green one, an orange one and a blue one, ahead of five smaller one-eyed aliens.

Wins need five or more matching symbols touching across or down, anywhere on the grid. Each cluster is removed once it pays, new symbols fall in to fill the gaps, and the cascades go on until no new cluster forms. A cluster pays only its highest win.

At $1, a cluster of five crowned reds pays $1 and one of 18 or more pays $1,500. The pink monster runs from 80 cents to $500, the green from 60 cents to $400, and the orange and blue from 50 cents to $250.

The one-eyed aliens pay far less: 20 cents to $40 for the cyan, purple and red ones, and 10 cents to $20 for the green and yellow.

Paytable page 10 in our demo session: the five two-eyed monsters at the 1.00 bet, from 5 symbols up to clusters of 18 or more. FluxPlays demo test, 19 October 2026.

Five bet buttons sit around the default, 0.50 to 2.00, with minus and plus for the rest. The server lists 17 coin values from 0.01 to 10.00 at 10 coins a spin, so a spin costs $0.10 to $100. The game collects every win itself, and there is no gamble.

Base spin 34 of 100 at $1, mid-round: the cascades have pushed the Experiment Charger to 21, with gaps still open on the grid. FluxPlays demo test, 19 October 2026.

Gargantoonz bonus features

Wilds, Fluctuation and Discharge

Wilds substitute for every symbol. Each round the game picks one one-eyed symbol type to fluctuate, and if that type wins, one or two Quantum Wilds appear where its symbols were removed. A round with no win at all may instead have 4 to 8 Quantum Wilds added to the grid.

Paytable page 1 in our demo session: five wild symbols, the Gargantoon among them, and up to 7000x your normal bet. FluxPlays demo test, 19 October 2026.

The Experiment Charger

While no experiment is running, every winning cluster charges the dial. Twenty symbols fill it, and once the cascades are done the game picks one of the three experiments at random.

An experiment starts by adding its own wilds, and every wild already on the grid turns into that kind. From then on only those wilds charge the dial, with the symbols they collect: 40 complete the experiment, and 40 more overcharge it. A completed experiment leads straight into another until all three are done; a failed one ends the cycle.

The Experiment Charger page of the paytable in our demo session: 20 symbols start an experiment, and success leads to the next. FluxPlays demo test, 19 October 2026.

Gamma Ray Burst, Black Hole and Supernova

Gamma Ray Burst adds 7 to 9 wilds. When one wins, it counts the symbols in its cluster, then removes and counts every other symbol of the same kind on the grid before it leaves.

Black Hole adds 4 to 6 wilds that wait on the grid until they win. When the cascades end, each one swallows every symbol touching it, diagonals included, and leaves to charge the dial.

Supernova adds 3 to 5 wilds. A winning one stays and steps one square diagonally on each new cascade, and when the cascades end it travels 8 steps, collecting what lies in its path. For all three, three or more of the same experiment wild in one cluster fire their effect at once.

The Gargantoon and the Gargantoonz feature

Every successful experiment feeds a second charger and evolves the Gargantoon in its tank. It starts at x1, and each overcharged experiment adds one, so the multiplier runs from x1 to x4.

If all three experiments succeed, the Gargantoonz feature plays in three steps. Eight 1x1 Gargantoon wilds land and stay even when they win; after the wins are counted they merge into two 2x2 wilds, which stay again, and then into one 3x3 wild that leaves with its win. Each carries the multiplier, though a cluster with several uses only one.

The Gargantoonz page of the paytable in our demo session: eight 1x1 Gargantoon wilds merging into 2x2 and then 3x3 wilds. FluxPlays demo test, 19 October 2026.

RTP, volatility and max win

The help text, the eleven paytable pages and the official game page state no RTP. Review sites list 96.20% as the top version, with versions as low as 84.20% for casinos to choose, and the practice demo does not show which one it runs. Most rate it high volatility and one mid-high.

The paytable sets the cap plainly: "Win up to 7000x your normal bet!", $7,000 at our $1. There is no bonus buy, no ante and no gamble.

Our Gargantoonz demo test

We counted each unlabelled practice credit as one dollar. The demo opened on 25,000.00 with the 1.00 button lit, 10 coins of 0.10, and all 100 spins ran there in one session with no reload. A script pressed spin each time, without Auto Play, and Fast Play was on from the start, which shortens the animations only.

The log and the screen agree to the cent: $100.00 staked, $24.60 returned, 24,924.60 at the close. That was the lowest point of the session; the highest, 24,999.20, came straight after spin 1.

Clusters landed often but paid little. Of 42 winning spins, 37 paid under $1, ten of them 20 cents and seven 50 cents. Only five spins reached $1 or more: $2.90 on spin 34, $1.80 on spin 63, $1.70 on spin 90, $1.50 on spin 45 and $1.30 on spin 64. The longest losing run was 5 spins, 18 to 22.

Spin 34 was the long one. Its cascades kept going until the dial read 21, past the 20 that fills it, as our capture shows, and the round settled at $2.90. No experiment followed at any point in our session.

The first 50 spins returned $13.30 and the last 50 $11.30. We never saw an experiment, a Gargantoon wild or anything near the cap, so those parts come from the rules. A hundred spins with no feature cannot tell you the RTP or the volatility.

Is Gargantoonz worth trying?

The experiment chain is the draw. Each stage has to succeed to reach the next, overcharging raises the final multiplier, and the Gargantoon wilds grow while they keep paying. With an 18-symbol cluster of reds worth $1,500 at $1 and a 7,000x cap, the top end is far above its base game.

That base game is the catch. Clusters of one-eyed aliens pay cents, the chain needs three experiments in a row before the Gargantoon appears, and there is no buy to skip ahead. Our session shows how thin the spins between features can be.

By both games' rules, Reactoonz is the model: the same 7x7 grid, clusters of five or more and Fluctuation. Its charger lines up Quantum features instead of experiments, and its single 3x3 Gargantoon splits into smaller wilds, where these Gargantoons merge upward and carry a multiplier. Its rules state no cap.

Gigantoonz is a different branch: an 8x8 grid, clusters of six or more, mega symbols and a 4,000x cap. Our three sessions returned $33.60 in Reactoonz, $30.70 in Gigantoonz and $24.60 here, single sessions without a top feature in any of them.