In this Bonanza slot review, we take a closer look at a popular online slot released by Big Time Gaming. Originally launched in 2016, Bonanza helped popularise the Megaways mechanic and quickly became one of the most recognisable games in the online casino market thanks to its dynamic reel system and cascading gameplay.
Set inside a gold mine, the game combines a mining theme with up to 117,649 ways to win, replacing traditional paylines with matching symbols from left to right across its 6-reel Megaways layout.
Even years after release, our Bonanza slot review found that the game still holds up extremely well thanks to its innovative mechanics, bonus potential, and highly engaging gameplay loop.
Game Overview
Bonanza is a 6-reel Megaways slot from Big Time Gaming built around a mining theme and cascading gameplay.
It uses a variable reel system that can create up to 117,649 ways to win on a single spin, depending on the number of symbols on each reel.
The gameplay revolves around cascading wins and a multiplier-based free spins feature, so Bonanza has more features than the average slots from this era.
| Game name | Bonanza |
| Theme | Mining |
| Provider | Big Time Gaming |
| Year of release | 2016 |
Game Features: Symbols, paylines
Bonanza uses the Megaways mechanics, and the number of symbols on each reel changes with every spin. Depending on the reel layout, the game can offer up to 117,649 ways to win. Wins are formed by landing matching symbols on consecutive reels from left to right, and all wins are evaluated and paid. Then, the winning symbols are removed before the reels cascade with new symbols falling into place.
One thing that stood out during our Bonanza slot review is how well the symbol setup ties into the mining theme. Premium symbols include colourful gems and sacks of gold, while lower-paying symbols are the standard card ranks from A to 10.
The Dynamite Wild substitutes for all regular symbols and helps complete winning combinations. A key mechanic in the base game is the Avalanche feature. Whenever a winning combination lands, the symbols involved disappear, and new ones fall into place, creating the chance for consecutive wins from a single spin.
Mining carts can also appear above reels 2 to 5, adding extra symbols and increasing the total number of ways to win. The free spins feature is triggered by landing 4 GOLD Scatter symbols, awarding 12 free spins and activating the game’s unlimited win multiplier mechanic.
Gameplay: Bonanza mechanics
One of the biggest strengths highlighted in our Bonanza slot review is how several mechanics work together in this game, which is even more impressive given that Bonanza is over a decade old.
Every spin starts with the Megaways reel system determining how many symbols appear on each reel. Wins are formed by matching symbols across consecutive reels from left to right, with up to 117,649 ways to win possible when the reels are fully expanded.
Whenever a winning combination lands, the Avalanche feature removes those symbols and drops new ones into place. This creates the chance for multiple consecutive wins from a single paid spin.
The Mining Cart modifier adds another layer to the gameplay. Carts can appear above reels 2 to 5 and add extra symbols to those reels, increasing the total number of ways to win for that spin.
Landing 4 GOLD Scatter symbols triggers the free spins feature and awards 12 free spins. During free spins, every winning cascade increases the multiplier by 1x, and there is no upper cap. Because the multiplier carries over throughout the entire free spins feature, bonus rounds can escalate quickly if enough cascades land in succession.
The feature can also be retriggered with additional Scatter symbols, giving the multiplier more time to build and increasing the chance of a major payout.
| Category | Details |
| Wilds | Yes |
| Scatters | Yes |
| Other special symbols | Mining Carts and GOLD Scatter |
| Gamble feature | No |
| Reel features | Megaways reels and Avalanche wins |
| Free spins | Yes |
| Respins | No |
| Multipliers | Yes |
| Other bonus features | Unlimited win multiplier in free spins |
RTP + volatility
Bonanza comes with an RTP of up to 96.00%, which is competitive when compared to other modern Megaways slots. As the exact RTP can vary by casino, it is worth checking the game information before playing.
Volatility is rated as high, and our Bonanza slot review aligns with that assessment. Regular wins do occur thanks to the Avalanche mechanic, but the higher multipliers generally appear in the free spins feature.
Payouts
The paytable in Bonanza has big gaps between the high and low paying symbols, but most of the game’s biggest payouts still come through the multiplier-based free spins feature rather than regular line wins.
Here are the highest symbol values for landing 6 matching symbols:
- Diamond – 50
- Ruby – 7.5
- Blue Gem – 2
- Green Gem – 2
- A – 1.75
- K – 1.75
- Q/J – 1
- 10 – 0.9
- 9 – 0.8
The values above are multiplied by your total stake.
For example, if you are playing with a £5 stake, landing 6 Diamond symbols (value 50) would pay:
50 x £5 = £250 win
The maximum win in Bonanza is up to 26,000x your stake, achieved through large cascades and high multipliers during the free spins feature.
| Category | Details |
| RTP | 96.00% |
| Maximum win | 26,000x stake |
| Highest-paying symbol | Diamond |
| Volatility | High |
Stake limits
One thing worth
noting in our Bonanza slot review is that the game uses a stake-based betting system rather than fixed paylines, since the Megaways mechanic determines the number of ways to win automatically on every spin.
Players can set their total stake between £0.20 and £5.00 per spin (£2 max for under 25s), with no paylines or bet-per-line settings to adjust manually.
| Category | Details |
| Minimum bet | £0.20 |
| Maximum bet | £5.00 (£2 for under 25s) |
| Adjustable paylines | No |
| Bet per line | N/A (Megaways system) |
| Buy feature | No |
Play Bonanza
Audiovisuals
While the mechanics feel highly modern, this Bonanza slot review noted that the audiovisuals look old-school. The visuals are clean and polished, but the art style is simpler than one would expect from newer Megaways releases, and the same goes for the rather simplistic sounds.
That said, the mining theme still comes across well through the gem symbols, wooden interface, and gold mine backdrop, all of which fit the setting nicely, but they look outdated.
Bonanza Slot Review: Summary
In this part of our Bonanza slot review, we wrap things up by evaluating how the game performs across the key scoring areas. While the presentation comes across as dated, the mechanics and gameplay hold up well.
Gameplay excitement (17/20)
The Avalanche system reel mechanic keeps spins engaging, and the potential for long cascade chains adds to the tension.
Bonus features quality (18/20)
The free spins round is excellent, with an unlimited multiplier that can build quickly during strong cascades. It remains one of the better Megaways bonus features.
Winning potential (14/15)
A 26,000x max win is still very competitive, especially considering the game’s age.
Volatility balance (9/15)
High volatility fits the game well, but long dry spells can make sessions feel frustrating when the bonus is not landing.
Theme and design (4/10)
The mining theme works, but the visuals now look quite dated and basic.
Replay probability (7/10)
Bonanza’s gameplay remains surprisingly highly replayable thanks to the cascading mechanic and fun bonus feature, although many players might not prefer the simpler graphics. The Bonanza demo version is avaialble at Unibet for those who want to test it.
User experience (7/10)
The interface is simple and easy to use, though visually it feels older than most modern Megaways slots. The controls are very straightforward, and the information tab is transparent and easy to understand.
| Category | Max score | Our score |
| Gameplay | 20 | 17 |
| Bonus features quality | 20 | 18 |
| Winning potential | 15 | 14 |
| Volatility balance | 15 | 9 |
| Theme and design | 10 | 4 |
| Replay probability | 10 | 7 |
| User experience | 10 | 7 |
| Total score | 100 | 76 |
