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Gem Rocks slot review

Added by Yggdrasil. Information last updated: 11/05/2020

User rating:

- (0)

Tester rating:

3.5 (1)

Game information

Game supplier:Yggdrasil

Release date:02/2018



Max. win:bet x 16384

Mobile version:Yes

Play Gem Rocks


Colossal symbols

Cascading reels

Max. lines


Max. win


Fairy tales & fantasy

Riches & luxury


User ratings (0)

Game design:



Game sounds:

Mobile gaming:


RTP (Return to player):
Max. win:
bet x 16384

Bojoko score (compared to other slots on Bojoko)
Yggdrasil score (compared to other slots of supplier)

Slot tester's review: Trystan Michielsen

Gem Rocks sees the mountains themselves come to life, crumbling down onto winning paylines and creating massive cascades!

Developed by Yggdrasil, Gem Rocks was released in 2018 and adds a slot to their library that leans heavily on the cascading reels feature. Other games that use this mechanic include Play ‘n GO’s Reactoonz and Tiger and Dragon by Red Rake Gaming.

The game has a sizeable 6-reel, 4-row playing field with a massive 4,096 ways to win. As the name probably gives away, the game is based around the combination of gems and rocks. The background shows us a pile of rocks as we look at the core of the mountain. The different symbols are all gems, embedded in rock.

I liked the overall look of the slot. It’s very clean and the symbols are minimalistic and brightly coloured. As the game hinges around the cascading reels feature, it’s nice that before the new symbols drop down the gems that could become a new payline light up slightly so you know what to look for.

The game keeps things simple when it comes to the sound. Most of what you’ll hear is the sound of rocks rumbling. When there’s a winning payline there is a rather orchestral sounding tune playing which picks up if the cascading reels generate more win. These fade out quickly once the wins stop coming.


The reels are filled with simple but original symbols, all gems that seem embedded into the rock. The rocks themselves are coloured matched with the gems to make it easy to tell apart. From highest to lowest they are:

  • Red Star: Max. 200 coins with six-of-a-kind on a winning payline.
  • Yellow Moon: Max. 35 coins with six-of-a-kind on a winning payline.
  • Azure Circle: Max. 25 coins with six-of-a-kind on a winning payline.
  • Blue Triangle: Max. 25 coins with six-of-a-kind on a winning payline.
  • Grey Pyramid: Max. 20 coins with six-of-a-kind on a winning payline.
  • Green Square: Max. 20 coins with six-of-a-kind on a winning payline.
  • Purple Diamond: Max. 20 coins with six-of-a-kind on a winning payline.
  • Orange Cross: Max. 20 coins with six-of-a-kind on a winning payline.


Gem Rocks is a simple slot with not a lot of features, but they work well together to create a fun experience. The game mostly plays itself with little input required from the player. The High Volatility also means that wins are rather rare but due to the cascading reels, if we consider that a single win it can get pretty big.

The main features of this game are:

  • 4,096 Ways To Win: As long as the same symbols appear on consecutive reels from left to right this will count as a win. Having more symbols on each reel will increase the total win.
  • Cascading Reels: Whenever there is a winning payline, the symbols involved will explode and cause the remaining symbols to fall down, making room for new symbols. This can create additional wins.
  • Colossal Symbols: After 2, 5 and 9 wins in a single spin respectively a 2x2, 3x3 and 4x4 colossal symbol will appear to help and create new wins.

Because of the low number of features, the gameplay is rather simple. The 4,096 ways to win help in creating wins which cause the reels to drop down and maybe create new wins. Once that happens enough the game adds a colossal symbol and so on. The 2x2 Colossal Symbol would show up often enough, the 3x3 Symbol was rare and I didn’t get to the 4x4 symbol at all. Considering its size we can imagine that will be quite a win so I understand why it’s sparse.

Everything is presented in a clear way where the different colours associated with the symbols help a lot. Each gem lights up a bit if they’re potentially part of a win while the reels are still dropping down. I found that to be a clever little addition that helped a lot.

I thought the gameplay was solid but not very special since there was so little interaction required. In the best-case scenario, the game would play itself for up to 9 times in a row due to the cascading reels. I was glad it looked so crisp and clear, however, since that at least made it interesting to look at!

In Conclusion

Gem Rocks is a simple slot that is made to look pretty. The symbols are big and obvious with distinct colours that helped in keeping things apart. The tracker on the left kept score as the cascading reels created new wins, making it clear when a colossal symbol would appear.

I liked that the art was all original, no tired old symbols this time, and the background made sure I felt like I was dealing with rocks and gems the entire time. The ability to pick a bet between C$0.10 and C$50 meant I was free in deciding how risky I wanted to play it. A max. win of 16,384x your bet should appeal to everyone!

I found games with cascading reels to often resemble each other since the premise is so dominant in a slot like this. With the addition of colossal symbols, I think Gem Rocks takes a big step in setting itself apart. The Colossal Symbols also appeared organically, although they didn’t often contribute to a win.

Are you looking for a classic slot with familiar features but a modern presentation? Then you can’t really go wrong with Gem Rocks. It offers a solid albeit passive experience where you’ll spend your time looking out for a winning streak that will get you the coveted 4x4 Colossal Symbol!

Overall rating:


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Wins and bets

RTP (Return to Player):96.2%


Max. win:bet x 16384

Min. bet:C$0.1

Max. bet:C$50

Progressive jackpot:

Reels & playlines



Non-standard layout:

Max. lines:4096

Min. lines:4096

Win both ways:

Other features


Expanding reels:

Stacked symbols:

Colossal symbols

Auto play:

Turbo play:

Quick play:

Virtual reality:

Bonus features

Bonus game:

Random bonus:

Progressive bonus:

Buy bonus:

Free spins:

Scatter symbols:

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Standard wilds:

Sticky wilds:

Walking wilds:

Stacked wilds:

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Walking re-spins:

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Cascading reels:

Sticky wins:


You can play Gem Rocks in English, Finnish, Swedish, German and 18 other languages.

All supported languages:
English, Finnish, Swedish, German, French, Spanish, Italian, Russian, Czech, Dutch, Greek, Hungarian, Polish, Norwegian, Portuguese, Romanian, Turkish, Chinese, Korean, Japanese, Thai


Gem Rocks supports GBP, EUR, USD, CAD


Release date 02/2018
44th newest on Yggdrasil 1,017th newest on Bojoko
RTP 96.2% 0.35% > average
38th highest on Yggdrasil 896th highest on Bojoko
Win up to 16384 x your bet
20th highest on Yggdrasil 246th highest on Bojoko
Paylines 4096 20380% > average
3rd highest on Yggdrasil 59th highest on Bojoko
Min bet C$0.1 per spin
6th lowest on Yggdrasil 480th lowest on Bojoko
Max bet C$50 per spin
60th highest on Yggdrasil 1,480th highest on Bojoko
Rated 0 by 0 members
2nd most rated on Yggdrasil 38th most rated on Bojoko
78 more slots listed by Yggdrasil

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Slot tester's profile


Trystan Michielsen

Trystan Michielsen

I've been playing videoslots for almost 10 years and been a professional reviewer for over 5. I look at slots not just as a writer but also as a player, hoping to help others find their perfect slot.

I also enjoy movies, books and travel so any slots with those topics usually have my preference. But in general I'll play everything!

Latest reviews:
Gem Rocks cover

Game supplier:Yggdrasil

Release date:02/2018

RTP (Return to player):96.2%

Max. win:bet x 16384

Mobile version:Yes

User rating: 0
Tester rating: 3.5

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