Castle of Terror

Castle of Terror Slot Review

Slot Provider: Big Time Gaming

RTP: 96.72% | Variance: High | Maximum Win: 61,720x

Our Score: 8.6

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About Castle of Terror

Reviewed by:

Published Date: 13th September 2022

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.

Castle of Terror by Big Time Gaming is high variance horror slot from October 2022 with 4,096 paylines and a massive 61,720x top payout. The game is in the comic-book style of Bloodsuckers by NetEnt or Immortal Romance from Microgaming, though with classier graphics.

There are thrilling moments as Holy Water triggers Wild Transformations and multipliers before free spins bring up the usual high jinks associated with BTG games. For the bonus rounds Holy Water lands on every spin and progressive multipliers persist between spins. There is even an enhanced bonus round triggered by special Gold Castle Scatters where multipliers start at 2x rather than 1x and increase by 1x with each Wild Transformation.

In short, fun atmosphere and with that blockbuster top payout, plenty of potential for things to go off in the usual BTG way!

Castle of Terror Game Information

  • RTP: 96.72%
  • Variance: High
  • Maximum Win: 61,720x
  • Progressive Jackpot: No
  • Reels: 6
  • Rows: 4
  • Paylines: 4,096
  • Minimum Stake: £0.20
  • Theme: Horror
  • Features: Wilds, Free Spins, Progressive Multipliers, Transforming Wilds

What We Liked

  • Massive top win value
  • Enhanced free spins = better multipliers
  • Wilds transform to add value to paytable
  • Creepy theme works well
  • Above average RTP

What We Didn't like

  • Not as feature-packed as Lil Devil
  • Tough to unlock free spins

Castle of Terror Review Scores

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

What Our Reviewer Says ...

"A classic high variance slot working free spins and progressive multipliers nicely to drive big wins!"

Overall Score: 8.6

Theme & Design

Our Score 8

Castle of Terror has the visual feel of a classic, vintage horror. The action takes place against the backdrop of a beautifully rendered country hillside, atop which sits a castle. The sun is shining, there are autumnal colors, a church yard and iron railings in the fore. But like all the best horrors, something sinister lurks and the feeling is that it can’t stay this way for long.

During the game, Holy Water bottles emblazoned with crosses smash over the reels whilst the free spins round takes you inside the castle at night to a candlelit room with lightning flashes outside. It’s not as scary as more adult-themed games of No Limit City, whose Book of Shadows and Mental are far darker in comparison, but instead has a knowingly kitsch ‘70s feel about it which is endearing and fun.

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.

The RTP of Castle of Terror is 96.72%, comfortably above average and giving you good value for your gaming.

As you would expect from Big Time Gaming, this is also a super-volatile game capable of kicking out some extraordinary wins as we shall see in this review. But also capable of frustrating the hell out of you as you chase down those payouts.

If you are into your volatility then check out our Top 20 high variance slots with some classics and off-piste picks too.

Maximum Win

Our Score 9

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 maximum win in Castle of Terror is 61,720x. That puts it right up there amongst BTG’s highest paying slots alongside games like Outlaw and Lil Devil. If you like that kind of prize money then you could also check our list of games with a max win higher than 100,000x.

Symbols and Paytable

Our Score 8

Castle of Terror follows a 4,096 paylines model with 6 reels and 4 rows to spin across. The high number of win ways come up because wins are triggered by landing identical symbols on adjacent reels – regardless of positions – from left to right.

The paytable shows good potential with premium symbols valued at up to 50x which gives you a lot of win power when combined with big multipliers.

Castle of Terror Paytable
Castle of Terror Slot By Big Time Gaming Paytable

Low payers are represented by the cards from 9 through to Ace with a max payout of 5x for six on a payline.

Meanwhile, premiums are the character symbols: the Gardener, the Maid, the Gentleman and the Lady. The Lady pays up to 50x for six on a payline.

Look out as well for Wilds which play a key role, substituting for all other symbols to form wins. They land as a big W and more appear in the transformative Holy Water feature. And finally there are Castle of Terror scatters – both silver and gold – which unlock the free spins round.

Features and Gameplay

Our Score 9

Despite being without Megaways™, Castle of Terror offers classic BTG gameplay in the form of a pulsating mix of wild transformations, progressive multipliers and the climax of a free spins round with enhanced modifiers.

Holy Water Triggers Wild Conversions …

The base game is all about a feature called Holy Water.

This triggered very regularly during testing29 times in 200 spins in fact. When it happens, night falls and a Holy Water bottle appears in front of the reels. It smashes and a shower of water splashes across them.

Two or more positions on the center four reels may be hit with water. If a premium character is in one of those positions, then it is converted into a wild and with each conversion, a global multiplier increases by 1x. You can see that at the top of the reels in the screenshot below. When the reels stop spinning, any wins are calculated and the multiplier is applied to all of them.

Holy Water Feature in Castle of Terror
The Holy Water Feature triggering

Three or More Scatters Triggers 12 Free Spins …

The base game showed itself to be a bit slow in testing and to really unlock the best parts of Castle of Terror you need to unlock the free spins rounds. This is done by landing 3 or more Silver Castle or Gold Castle Scatters. That gets you 12 spins, with 3 more spins for each additional scatter appearing on the reels.

How is the free spins round more rewarding? Well, on EVERY spin, the Holy Water bottle appears, so that’s more wilds and more multipliers.

And … because the multiplier does NOT re-set between spins, it just keeps growing adding more and more value to every win.

And if you can drive that multiplier up to 20x, you’ll trigger an additional 6 free spins.

With Gold Castle Scatters You Enter Enhanced Free Spins

Big Time Gaming like an enhanced free spins round – see Wild Flower for another example. In this case, if one of your triggering Scatters is a Gold Castle, then you enter the Enhanced Free Spins round.

That means, your multiplier starts at 2x and increases by 2x with each Wild conversion. And just like the standard free spins, Holy Water is going to land on EVERY spin.

Whilst the Enhanced Free Spins is the better of the two, those Gold Castles are a big rarity, so use them well when they drop.

And If You Win 100x of More You Can Exchange To Enter Free Spins

Getting into the free spins round is what it’s all about and so BTG have also added another option – you can exchange wins for free spins, or the chance for free spins.

Firstly, any win over 100x can be swapped directly for entry to the standard free spins. Then, any win of 25x to 100x can be swapped for the chance to gamble for free spins on the spin of a wheel.

Land on green, you get 12 spins. Land on red, you lose everything!

The Final Verdict

Castle of Terror is another top quality, high variance slot from BTG. It ticks all the boxes – volatile maths model, cool theme, big top win, and progressive features that suggest massive payouts are possible on rare occasions when a win sequence unfolds in the rigiht way. Those who enjoy games like Lil Devil or The Final Countdown (both 4,096-win-ways slots too) will get their kicks here.

It’s worth pointing out though that Castle of Terror isn’t quite as intense as Lil Devil – it doesn’t have Sticky Wilds and the multipliers are unlikely to hit the highs of 144x. But, it’s max win of 61,720x is significantly higher than that of Lil Devil (36,403x) which suggests it could deliver on a bigger scale on occasion.

Of course, when reviewing these high risk games we always add the caveat that whilst Castle of Terror may bring drama, it will also frustrate more often. So be ready for some sessions without many wins before you hit pay dirt.

Compare Castle of Terror With Similar Slots Picked By Us

Here are more games like Castle of Terror compared on configuration and features. Click through to read a review of each one.

Slot GameProviderThemeMin. StakeMax. RTPVariancePaylinesTop PayoutJackpot
Nolimit CityHorror£0.2096.09%High243 Upwards23,237xNo
Hacksaw GamingGhosts£0.1096.25%MediumCluster Pays5,000xNo
Hacksaw GamingHorror£0.1096.19%High1010,000xNo
Hacksaw GamingHorror£0.1096.29%High1010,000xNo
Nolimit CityWild West£0.1096.08%High108+300,000xNo
Relax GamingPirates£0.1096.29%High4050,000xNo
Big Time GamingMusic£0.1096.59%High4,096114,100xNo
Big Time GamingParty£0.2096.54%HighGrid Slot66,960xNo

Who Made Castle of Terror?

  • Name: Big Time Gaming
  • Established: 2011
  • UK License: 38696
  • Total Games: 55 +
  • Known For: Inventing Megaways, super volatile slots, high max payout slots, rock n roll soundtracks
  • Popular Slots: Bonanza Megaways, Max Megaways, Outlaw, Danger! High Voltage
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