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You can try Mental for free right here and test the slot’s features, theme and bonus rounds before deciding if you want to play it on a real money version.
The main game has a default RTP of 96.08%, and if you decide to buy the most expensive free spins option (Mental Free spins), you’ll play with a default RTP of 96.68%.
It would help if you were careful, though, as Mental comes with two versions. Some casinos offer Mental with an RTP of 96.08%, but others do so with a lower RTP of a mere 94.20%.
RTP comparison for Mental
It’s a waste of money to play the lower-paying version of Mental, so you need to check the game rules of your casino before you play.
You can also let the Wizard do the work for you, who has already selected all the casinos with the 96.08% RTP version.
You also see which casinos you need to avoid, as these offer the lower RTP version.
Why RTP is important when playing slots
Whether we like it or not, the Return to Player, or RTP, of a slot significantly impacts a lot of crucial elements that come with playing slots.
The RTP is another term for the average percentage that a slot pays back for each stake. So, when a slot has a 96% RTP, it will pay back, on average, 96p for each pound staked. As you can imagine, the higher the RTP, the better it is for you, the player, as this will result in:
More spins before your money runs out
More spins = more chances to win
Increased playing time for the player
More value for money for the player
A lower profit margin for the casino
History of RTP and online slots
In the “old days”, all online slots had a default RTP, meaning the Return to Player was the same for each slot, no matter which online casino you played it in. However, since around 2020, due to regulations, increased Gambling Taxes and rising costs, online casinos started pressuring slot providers to release slots with different RTP configurations.
In effect, the online casino now had a choice: it was now able to offer its players a lower-paying RTP version. You could be playing a specific slot with a 96% RTP at casino A, and play the same slot with a 94% RTP at casino B, without even knowing it. The slot may look and feel the same, but the maths model underneath, which is the heart and soul of a slot, may be different, with all the negative consequences that come with it.
An example in real numbers
To illustrate the difference between playing a high-RTP slot versus playing the same slot but with a lower RTP, we have done some calculations.
Let’s take, as an example, one of the most popular online slots ever made: Book of Dead by Play’n GO. It has five possible RTP configurations: 84.18%, 87.25%, 91.25%, 94.25%, and 96.21%. Of course, other slots have different payout percentages, so results will vary.
We have calculated for Book of Dead, per RTP configuration, how many spins it takes to run out of money, based on theoretical losses (house edge) per spin, a starting balance of £100 and a stake of £1 per spin.
Book of Dead RTP
Theoretical Playtime
House Edge
96.21%
2,612 spins
3.79%
94.25%
1,721 spins
5.75%
91.25%
1,131 spins
8,75%
87.25%
776 spins
12.75%
84.18%
625 spins
15.82%
As you can see in our calculations, there are huge differences in the number of spins when you compare the different RTP configurations. The difference between the 96.21% RTP and the 94.25% RTP version is over 900 spins!
Conclusion
Playing with a higher Return to Player increases your chances of winning and playing time. So, when you want to play an online slot, always try to find a casino that offers it at the highest payout setting.
Why RTP is important when playing slots
Playing with a higher Return to Player increases your chances of winning and playing time.
How to play
Mental has 5 reels and a 3-2-3-2-3 setup. Perhaps uncommon, but that’s what Mental is all about.
It’s a win-all-ways slot, with at least 108 ways to win.
Symbols can (occasionally) split into two.
There are also some enhancer cells, creating additional symbols on the reels.
All in all, getting tens of thousands of win ways is possible.
The premium symbols are the five numbered Patient Symbols.
We have the Organ Symbols as the lows.
The gold-coloured skulls are the Wilds.
You’ll also note the gold-coloured Tomb Stones or “Dead Patient” symbols.
Land one of these, and these transform into a Patient Symbol with an x5, x10, x15, x30, x50, x100, x200, x500, x1000, or even an insane x9999 multiplier.
You trigger the Mental Transform feature if you manage to land the so-called Spider symbols on reels 2 and 4. In that case, both Spider symbols transform into an xWays, xSplit, Dead Patient, Wild, or a Patient symbol.
Free spins bonus explained
If you thought the base game was complex, you’re right.
And it gets even more so, as we also have three free spins options: The Autopsy Free spins, Lobotomy Free spins, or the Mental Free spins.
To trigger these, you need to spin Scorpion symbols.
You can also use the Bonus Buy feature (Nolimit Bonus feature) to activate these.
The cost is 80x, 230x, or a monstrous 1000x the original bet.
If you like to gamble, you can select the Lucky Draw Free Spins option (cost: 232x). In that case, you trigger one of the three free spins options as described.
What is the max win on the Mental slot?
It’s probably a “no-brainer” that we’re talking about an extremely high variance slot. The maximum win is a flabbergasting 66,666x the stake.
The chances of winning it are 1 in 18 million spins, which is a great max win probability.
If you have a big bankroll, you can opt to buy the Mental Free spins, which is the way to get a fair chance at winning something in tens of thousands of times the bet. Be aware: this slot is very volatile, and your money can evaporate quickly if you find yourself on the wrong side of the variance.
CasinoWizard’s verdict: 8 out of 10
Nolimit City has done everything within its capabilities to pull out something extraordinary.
The unequalled theme, the mysterious and “psychotic” characters, and the outrageous win potential make this slot one to remember.
However, this isn’t a slot for novice players or those who avoid risk. It’s incredibly volatile and complex. Bear that in mind before you enter the hospital!
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