Big Fin Bay

Big Fin Bay Slot Review

Slot Provider: Thunderkick

RTP: 96.14% | Variance: High | Maximum Win: 15,040x

Our Score: 8.2

Play at Barz Casino

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About Big Fin Bay

Reviewed by:

Published Date: 15th April 2021

How We Review Slot Games

We test and rate all slot games across 5 criteria, assigning a score out of 10 for each and an overall score that is an average of the 5. To build an accurate assessment of each game we gather information from the supplier and play in real play or demo mode. Find out more.

Big Fin Bay is a six-reel fishing slot from Thunderkick with a high variance and expanding reels. Throughout the game wild symbols expand to full reel height and a mystery wilds feature turns up to 3 reels wild. At any time landing scatters gets you up to 36 free spins for a bonus round where expanding wilds trigger re-spins as well as expanding their reels by an extra row for the remainder of the round. 5,040 win ways in the base game can grow to as much as 117,649 in the free spins round in this way.

The game has a good max win of 15,040x and spins start at just 10p.

Big Fin Bay Game Information

  • RTP: 96.14%
  • Variance: High
  • Maximum Win: 15,040x
  • Progressive Jackpot: No
  • Reels: 6
  • Rows: Up to 7
  • Paylines: Up to 117, 649
  • Minimum Stake: £0.10
  • Theme: Fishing
  • Features: Expanding Wild, Mystery Wilds, Free Spins

Testing Notes: Here’s What Happened When We Played Big Fin Bay

IMPORTANT: To give you an accurate assessment of the games we review our writers play 200 spins. Whilst this is a useful tool to help us review games and to give an example of what might happen when you play, keep in mind that 200 spins is only a very small sample and cannot be used to accurately predict what might happen over another 200 spins. The outcome of all slots play is always random.

Boom Or Bust? Our Session By The Numbers

I played 200 spins on Big Fin Bay for free at Casumo Casino to test the game and this is what happened.

  • Stake Size: £1
  • Start balance: £5,000
  • End balance: £5,233.70
  • Hit Rate: 21% (42 winning spins in 200)
  • Biggest Win: 233.3x
  • Free Spins Round: 1
  • Session Time:  19 minutes 10 seconds

This was a particularly fruitful session.

Base game wins were always small, in fact rarely more than 2x – which makes sense looking at the low values in the paytable – and the hit rate was a moderate 21% which isn’t bad but not huge. But the features were a different story, triggering some very good wins, including a 233.3x when the free spins round eventually dropped after 180 spins.

The two Wild features – Mystery and Expanding – were especially useful. The expanding Wilds feature triggered 11 times over 200 spins (5.5%) producing a nice 46.8x win at best. A tip here: it helps if the wilds are on reels 1, 2 and 3, as they can start the win ways rather than completing lines. Meanwhile, the Mystery Wilds dropped just 3 times over 200 spins (1.5%) but produced solid enough wins of 19.8x and 42x (as well as a zero).

A 233.3x win from free spins on Big Fin Bay
A 233.3x win in testing from the free spins round

The free spins round took a long time to arrive but when it did was spectacular. I got 12 spins, of which 4 dropped expanded wilds to trigger re-spins and expand the rows. By the end I was playing with 18,900 win ways on each spin. This was a particularly good run, and it won’t always happen like this, but it does show how the cumulative effect of expanding reels and re-spins with expanded wilds can be highly lucrative.

What We Liked

  • Mystery Wilds and Expanding Wilds fill entire reels
  • Re-spins with expanding wilds in free spins round are lucrative
  • Nice, simple design and illustrative style
  • Grow the reels to have up to 117,649 paylines in free spins
  • Big 15,040x win potential

What We Didn't like

  • Highly volatile so can blow hot and cold

Big Fin Bay Review Scores

  • Theme and Design 8
  • RTP and Variance 9
  • Maximum Win 8
  • Symbols and Paytable 7
  • Features and Gameplay 9

What Our Reviewer Says ...

"A fun, offbeat fishing slot with an alternative take on the expanding reels engine and bags of big win potential!"

Overall Score: 8.2

Theme & Design

Our Score 8

Retro Fishing Slot Vibes But Still Highly Volatile

Big Fin Bay is an odd-looking game with a definite retro feel of back-to-basics graphical styles – you could almost be looking at something pinned on the wall of a seaside café in the 80s. The backdrop is a glistening Mediterranean seashore where fishing boats glide by, whilst front and centre sits your six-reel grid. On that grid are illustrated symbols that have a childlike quality to them and include a white bearded captain straight from a TV commercial.

Big Fin Bay by Thunderkick
Big Fin Bay – Retro fishing slot vibes

Whether you enjoy this style will be a matter of taste but after a few spins I came to like it – there is something comforting about the simple graphics and sea shanty soundtrack.

RTP and Variance

Our Score 9

What is RTP?

RTP (Return to Player) refers to the amount a game will pay out in cash prizes expressed as a percentage of all the money wagered on that game. For example, a 96% RTP means a game will pay out £96 for every £100 wagered. This is an average number and will vary from one session to the next.  Read more here.

What is Variance?

Variance refers to how far a game will deviate from its RTP over time. High variance games deviate a lot and produce uneven win distributions and unexpected windfalls. Low variance games provide a more stable and even distribution of wins. Read more here.

Like many Thunderkick slots, Big Fin Bay has an RTP of 96.14%. That is about average and promises good return on your wagering. This is also one of Thunderkick’s more volatile games so it can be a tough play with an uneven win distribution. But of course, on the flipside, it can kick out some huge wins too!

Maximum Win

Our Score 8

What Is Maximum Win?

Maximum win refers to the maximum amount a player can win from one spin. It is expressed as a multiple of the stake. For example, where the maximum win is 100,000x, from a £1 stake, the maximum win would be £100,000.  

The top payout is a massive 15,040x. That is big, though in recent years Thunderkick have stretched the win potential of their games further. For example, Gods of Rock comes in at 20,000x and Esqueleto Explosivo 2, their Mexican Day of the Dead game, comes in at a whopping 50,000x. You can find more high potential slots in our list of games with the highest max wins.

Symbols and Paytable

Our Score 7

Big Fin Bay is a 6 reel game with a variable number of rows per reel on each spin. There can be anywhere between 2 and 7 rows. But the number of win ways is always 5,040 in the base game. It will rise as high as 117,649 in the bonus round as we will see.

Big Fin Bay Paytable
The paytable with 7x for 6 captain symbols

You need to land 3 or more identical pay symbols – except for the Captain who pays for 2 or more – along a payline from left to right, starting with the left most reel, to trigger a win.

If you browse the pay table you will notice that pay symbols have only moderate value, but that is offset by the fact that you have so many ways to win of course.

There are 11 pay symbols in total. The low payers are the cards 9 through to Ace. These are valued at from 0.3x for 3 9s up to 1.5x for 6 Aces. The premiums are the 4 fish and the captain himself. These are valued at from 0.8x for 3 of the blue fish up to 7x for 6 of the captain symbols.

There is also a Marlin Wild symbol that substitutes for any pay symbol to complete a win way but does not have any pay value of its own. It can also expand to fill a reel as explained in the next section.

Features and Gameplay

Our Score 9

This is not a complicated slot. Everything happens around wilds and free spins. Here is how it works.

Expanding Wilds and Mystery Wilds

In the base game, if a wild forms part of a win then it expands to full reel height to potentially trigger further payouts. You may also see the Mystery Wild Feature trigger at any time. In this event, up to THREE reels become completely wild.

Expanding Wilds in Big Fin Bay
Expanding Wilds on reels 1 and 2 in testing
Mystery Wilds feature in Big Fin Bay
The Mystery Wilds feature turns reel 2 wild in testing

Up To 36 Free Spins With Re-Spins and Expanding Wilds

That’s all good but what you are really counting on for those big payouts is the free spins round to drop. You need three or more bonus anchor scatters to trigger this. For each scatter you will get up to SIX free spins.

Across six reels that makes up to 36 free spins!

Big Fin Bay Free Spins Round
Up to 6 spins are awarded for each reel showing a scatter

Now the Wilds have added value – each time they land they expand AND trigger a re-spin. When that re-spin happens, the wilds expand their reel by 1 more row to increase the paylines in play. These expanded reels persist in expanded format for the rest of the free spins.

A Wild Respin in Free Spins in Big Fin Bay
A wild repin during the free spins round in testing

And … if you can expand a reel to seven rows high, then you earn yourself 3 extra spins.

And for those who like the numbers (and Megaways™), six reels expanded to seven rows high is equal to the magic 117,649 paylines!

The Final Verdict

The simple design style of Big Fin Bay belies the highly volatile game engine lurking beneath the surface. In our 200 test spins the game revealed its true qualities and this is another excellent slot from a studio known with a reputation for top products. Both mystery wilds and expanding wilds can deliver big wins on their own in the base game but its the bonus round that will excite high risk slots fans the most where a powerful mix of full reel wilds, re-spins and expanding wilds is perfectly poised to produce blockbuster payout thrills when the game hits its stride. Top stuff and definitely worth a spin.

Useful Tips When Playing Big Fin Bay

Remember, online slots are games of chance, there is NO strategy that can improve your odds of winning. However, reading our review and following these tips will help you get the most out of your time playing this slot game.

1. Expanding and Mystery Wilds Are Best On Reel 1, 2 and 3

To give yourself the best chance of scoring wins with the expanding wilds you want to land them on reels 1 to 3 where they can start a win line. I had a 46.8x win from expanders on reels 1 and 2 in testing in this way.

2. Start With a Low Stake

This is a highly volatile slot and although I had a very profitable session in testing in reality it can also be very tough. It pays to start with a low stake and stretch your balance out whilst trying to chase down those big wins.

3. Play With A Thunderkick Slots Bonus

You can play this game with almost all of the match bonuses on our site. For example, Grand Ivy are offering a 100% match up to £300 which is available to spin on Big Fin Bay. That is a lot of bonus money to test your luck with!


4. Only Play At Licensed Slot Sites

We recommend the sites on this page because they are licensed by the UK Gambling Commission and offer fair, safe and secure slots play. Never play at unlicensed sites where your money is not protected and the games may be rigged.

Who Made Big Fin Bay?

  • Name: Thunderkick
  • Established: 2012
  • UK License: 40165
  • Total Games: 55
  • Known For: Quirky, eccentric slots with fun features and distinctive designs
  • Popular Slots: Pink Elephants 1 and 2, Flame Busters, Birds on a Wire
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