Ribs’ Golden Crypt takes us underground to meet Ribs, a rather suspicious skeleton who has somehow managed to lose the keys to his own treasure-filled crypt. Slotmill goes for a playful Halloween look rather than straight horror, filling the 6×6 grid with glowing ghosts, pumpkins, gems and plenty of gold. The cartoon style works nicely, although anyone familiar with the studio’s recent cluster slots will recognise quite a lot of the overall structure.
The interesting part is how the multipliers build during a winning sequence. Giant Symbols can increase the current Win Multiplier, while Multiplier Meteors wait on the grid until the Avalanches finally stop and then strengthen it further. Every winning round also creates a wild in an empty position, giving the sequence another chance to continue. Free Spins make the whole system considerably better by keeping the multiplier between spins instead of sending it back to the beginning.
Ribs’ Golden Crypt uses a 6×6 grid with Cluster Pays and Avalanche wins. A cluster requires at least 5 matching symbols connected horizontally or vertically. Winning symbols explode, new ones fall into their places and the process repeats for as long as another cluster forms. Whenever a round produces a cluster win, a wild is also created in a random empty position to help keep the chain moving.
The highest RTP is 96.01%, with a 94.03% version also available. Volatility is very high, the maximum win reaches 10,000x the bet, and stakes range from 0.20 to 100. Slotmill has not published an official hit-frequency figure. The maths are therefore very much geared towards occasional stronger sequences, and most of the serious potential comes from combining several Avalanche wins with Giant Symbols or Multiplier Meteors.
Every winning cluster disappears from the grid and starts an Avalanche. Symbols above fall into the empty positions and new ones arrive from the top, with the process repeating for as long as new clusters keep forming.
A winning round also creates a wild in a random empty position. The wild substitutes for regular paying symbols and can make it easier for the Avalanche sequence to continue.
Giant Symbols arrive with multipliers from 2x to 10x. When one participates in a winning cluster, its displayed value is added to the current Win Multiplier.
That multiplier belongs to the whole game round rather than just the individual Giant Symbol. In the base game it resets at the beginning of the next spin, so the strongest results need the Avalanche chain to continue long enough for the built multiplier to actually matter.
Multiplier Meteors can carry 2x, 3x, 5x, 7x, 10x, 20x or 100x values. When one lands during a winning round, it remains on the grid until no more Avalanche wins are available.
At the end of the sequence, all active Meteor values are added together and applied to the current Win Multiplier. This means a round that has already collected Giant Symbol multipliers can receive another substantial boost right at the end.
Landing 3, 4 or 5 Bonus Keys awards 8, 10 or 12 Free Spins. The important change is that the Win Multiplier no longer resets between spins, so every Giant Symbol and useful Meteor can contribute to a multiplier that keeps developing throughout the feature.
When Free Spins trigger, they can also be randomly upgraded to Super Mode. In this version, a Giant Symbol is guaranteed at the beginning of every Free Spin, giving the persistent multiplier a much better chance to keep growing.
Slotmill includes several paid options for players who want to reach the main mechanics more directly.
Fast Track and Xtra-Bet cannot be active at the same time. The prices climb quickly, especially for Super Mode, but at least the menu lets you choose between simply increasing bonus frequency and skipping directly to a specific feature.
Ribs’ Golden Crypt gets the important part right: the multipliers actually give the Avalanche chains somewhere to go. Giant Symbols gradually strengthen the round, Meteors can add another sizeable boost at the end and the extra wild gives a good sequence another chance to keep going. Free Spins are clearly the strongest part because the persistent multiplier turns every useful hit into progress that can matter several spins later.
The downside is that the structure feels quite familiar for Slotmill. Cluster Pays, Avalanches and multiplier-heavy bonuses are hardly new territory for the studio, and the very high volatility means the mechanics can spend plenty of time looking more exciting than they actually pay. The Halloween presentation has charm and the multiplier system is well put together, but it stops just short of feeling genuinely fresh.
Our rating: 7/10
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