Thunder Coins: Hold and Win - the Rules, Restated
Verdict first: a three-reel Hold and Win with five fixed lines, one bonus engine and no hidden clauses. This page restates the build's full rule set - the footer reads version 0.11.1 - as multiples of your stake. The demo runs right here beside the rules. Check every number against the screen; that is what it is for.
Quick spec
| Board | 3 reels x 3 rows |
| Lines | 5, fixed, pay left to right; highest win per line only |
| Stake range | 0.20 - 100.00, nineteen steps |
| Jackpots | Mini 25x · Minor 50x · Major 150x · Grand 1,000x the stake |
| Advertised max win | 5,150x - the studio's guide for operators, a simulation record; not on the info screens |
| RTP line in the rules | Absent in this build; 95.66% in the studio's guide for operators |
| Feature buy | None in this build |
| Build | Playson demo, VER 0.11.1 |
Board, lines, stakes
Three reels, three rows, five fixed lines. Lines pay left to right and only the highest win per line counts. Stakes run from 0.20 to 100.00 in nineteen steps. Autoplay and hold-for-turbo sit on the main screen, one control each. Malfunction voids all pays and plays, the standard clause from the last info screen.
Paytable in stake multipliers
| Symbol | Three on a line |
|---|---|
| Wild (red 777) | 50x |
| Bells | 30x |
| BAR | 20x |
| Watermelon | 16x |
| Grapes | 16x |
| Plum | 4x |
| Orange | 4x |
| Lemon | 4x |
| Cherries | 1x |
Values match the build's own paytable at a 1.00 stake, where cash equals multiplier. At any other stake the screen shows cash and the ratio holds. The Wild substitutes every symbol except Bonus and Thunder Bonus, and it doubles as the top line pay. Cherries at 1x are the floor. The gap between 50x and 1x is the whole line-game economy. The lines keep the meter moving and the bonus engine does the paying.
Trigger geometry
The Bonus coin lands on reels 1 and 3 only. The Thunder Bonus - the lightning in the gold ring - lands on reel 2 only. One coin per outer reel plus a Thunder Bonus in the middle column is the shape every trigger takes. That split matters when you read a near miss: two coins on the outer reels mean the middle already decided.
Any Bonus coin landing in the main game can also trip the Pile of Gold feature. It throws extra Bonus and Thunder Bonus symbols onto the board, enough to activate the Bonus Game or more. The rules do not price its odds. Unverified stays unverified.
The Bonus Game, step by step
The round starts once every reel carries at least one Bonus symbol on the same spin. The board clears, and from there only Bonus coins and Thunder Bonus symbols land. Each coin prints its value on its face - x1, x2, x3, x5, x7, x10 or x15 the stake. Three re-spins open the round on the cleared board. Every incoming symbol puts the counter back at three, and the round ends when it runs dry. The values gathered in the Thunder Bonus symbols then pay as one total.
Four jackpot coins can drop during the round - Mini at 25x, Minor at 50x, Major at 150x, Grand at 1,000x. They land as board symbols, not as a side wheel, and their printed tier pays with the rest. The longest round in our own session ran 24 re-spins, and the pool's median round paid 48x. The engine runs on small resets. Length buys chances, not guarantees.
The Thunder Bonus, as sold and as logged
The lightning is a collector. When it lands together with any Bonus symbol in view, it sweeps the printed value of every coin on the board - jackpot coins included - and adds the sum to the spin win, or to the running total inside the Bonus Game. The intro screen sells this as the game's headline, and our own session backs it. The symbol sat on reel 2 through all 16 logged rounds of session TCHW-20260729-01, as the trigger rule requires, and each round paid exactly what its collectors held. In the main game it paid coins on 54 of 2,960 spins, 381.00 in total at a 1.00 stake. The rules promise no frequency. One session is a sample, not a rate. Both facts belong on the same page, which is why this page exists.
The number this build does not print
There is no RTP line anywhere in the info screens. The review's 95.66% comes from Playson's guide for operators. A Romanian copy of it lists 94.66%, 92.66% and 90.00% underneath. I log what the build pays and publish that instead: 100.84% across 6,343 pooled spins, session detail in the review. Two numbers, two different things measured. Treat the first as a claim and the second as a sample.
- Rules restated, not quoted. The exact wording sits on the info screens inside the demo.
- Jackpot and paytable values scale with stake and are shown here at the 1.00 reference.
- No buy menu exists in this build. The reels are the only route in.
- Feature frequencies - unpriced by the provider, unverified by us.
- The Thunder Bonus counts on this page come from one session of the three in the pool. The two sister logs were not recounted.
Quick answers
How does the Bonus Game start in Thunder Coins?
Reels 1 and 3 must each show a Bonus coin and reel 2 a Thunder Bonus on one spin. The Pile of Gold feature can top an incomplete set up to the full trigger. Three re-spins open the round and every arriving coin resets them to three.
What does the Thunder Bonus symbol actually do?
It collects the printed value of every coin in view, jackpot coins included, and adds the sum to the win. It lands on reel 2 only and works in both the main game and the Bonus Game. No Bonus Game starts without it, and in our own session it paid coins in the main game on 54 of 2,960 spins.
Can I buy the bonus in this game?
No. This build sells no feature entry - the reels are the only route. Stakes from 0.20 to 100.00 are the only lever the interface offers.
Is the free demo the same game as the paid version?
Same rules screens, same paytable, virtual balance. The demo on this page is the build our session ran on. Free play still means 18+, and the full session record sits behind the review.
Verified against
Session TCHW-20260729-01 - 2,960 spins of the 6,343-spin pool, July 2026, checkpoint discipline throughout. The info screens sit in the session archive. The session tables, screenshots and the score live in the Thunder Coins: Hold and Win review. The launch build is on the demo shelf, and the protocol is on the methodology page. The Hold and Win family itself is charted on a separate page, seven carriers side by side. What this page did not verify - feature frequencies beyond one session, and the Thunder Bonus counts of the two sister logs. Both go on the list for the next build. 18+ applies to every mode of this game.
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