Fourth respin of a demo round, my counter had just snapped back to 3 for the third time, a Boost train sat parked on the centre reel, and an x3 tag blinked onto reel 1 right as it swept a fat coin. That single spin turned a limp 12x into something I actually leaned forward for. So let’s talk about how this feature works, because the mechanic is the whole story.
The trigger recipe
Royal Express is picky about how the round opens, and once you know the shape you’ll spot near-misses everywhere. Two ingredients have to arrive on the same spin, and they have to sit in exact spots.
Here’s the recipe as pure reel geometry:
- Reel 2 (the middle reel): a Boost train, and only there. It’s the collector that runs the round.
- Reel 1: a Bonus symbol.
- Reel 3: another Bonus symbol, mirroring reel 1.
Boost in the centre, a Bonus guarding each flank. That’s it. The pattern is so specific that I spent whole demo stretches watching a Boost land with just one Bonus beside it, no cigar, which is exactly why the Pile of Gold back door (further down) matters so much.
Three respins that keep resetting
You start with 3 respins.
It’s the classic hold-and-win engine underneath: symbols that land lock in place, and the empty cells spin again. The rule that makes the whole thing tick is the reset. Every time a fresh symbol lands and sticks, the counter jumps straight back to 3, so a round doesn’t end on a timer, it ends on a cold streak. Keep catching tiles and you keep buying respins. Go three spins with nothing new, or fill the grid completely, and the round’s done. My best demo run reset the counter five or six times before it finally ran dry, and that “will this one extend it” tension is genuinely where the fun lives.
Nobody gets a fixed number of spins here, which is the clever bit.
What the Boost actually does
The Boost train is the payout engine. As the respins roll, it collects the cash values printed on the grid, including any jackpot values sitting there, and pockets them into your running total. Bonus tiles land carrying their own amounts, the Boost sweeps them up, and a round that keeps resetting keeps feeding the collection. One thing to set expectations: there’s no separate free-spins round bolted on. These collection respins are the entire feature, so everything you win comes from this one loop.
Multipliers, and the stacking rule
During the bonus, random Royal Express multipliers surface on reels 1 and 3 as x1, x2 or x3 tags. A lone x1 does nothing you’d notice. An x2 or x3 arriving on a spin that’s already scooping decent coins is where the memorable rounds come from.
Now the part that’s unique to this feature, and the reason I kept staring at those outer reels.
If two multipliers land on the very same cell, their values add together rather than replacing each other. So an x2 and an x3 stacking on one position give you x5 on that cell, not x3. It doesn’t happen often, since you need two tags to hit the identical spot, but when it does the swing is real. In my sessions I saw plenty of plain x1s and x2s and comparatively few x3s, so the game keeps the ceiling honest even before you factor in how rarely two of them collide.
Pile of Gold
Because the standard trigger is so fussy, Playson built in a relief valve called Pile of Gold. It fires at random during ordinary base spins and seeds enough Bonus and Boost tiles to launch the whole round for you, no exact pattern required. The game just decides you’re getting a bonus and hands it over.
I only caught it a few times across my demo balance of 11,000, but each hit flipped a dead spin into a full feature, and it means you’re never entirely hostage to fishing that centre Boost yourself.
Where the jackpots sit
Four fixed jackpots live inside the round: GRAND, MAJOR, MINOR and MINI. Mechanically they behave like any other grid value. When a jackpot symbol lands and locks, the Boost collects it just like a cash coin, folding it into your total. The GRAND is the top tier and stays stubbornly rare, while the smaller two turn up often enough to keep a stalling round from feeling pointless. Across my runs I only ever brushed the lower rungs, which is exactly what you should plan for. For the actual cash multiples and how they stack toward the max win, that’s a separate page: see the max win and jackpots page.
The catch
Fun as this feature is, I’ve got gripes. Without a lucky Pile of Gold you can spin a long stretch and never see the trigger assemble, since needing a Boost dead-centre with Bonuses on both flanks is a tall order. Payouts skew modest too: the GRAND barely shows, the everyday reality is the smaller collections, and the per-tile amounts aren’t cleanly published, so you’re trusting figures you can’t pre-check. Call it a satisfying build with a mean trigger. Strictly 18+, set a budget and walk when the fun runs out.
Want the mechanic without the wait? A Bonus Buy (around 75x the bet) drops you straight in, and I cover it on the Bonus Buy page. For the base controls and reaching the round the honest way, see how to play. For the full verdict, head to the main Royal Express review.
FAQ
What exactly triggers the Hold and Win bonus?
You need a Boost train on the middle reel (reel 2) and a Bonus symbol on both reel 1 and reel 3 on the same spin. That precise pattern opens the round. Pile of Gold can also seed the feature at random during base play, no pattern required.
Do the x1, x2 and x3 multipliers add up?
Yes, if two of them land on the same cell their values sum. An x2 and an x3 on one position make x5 on that cell. They appear randomly on reels 1 and 3 during the bonus.