lab studies / book of dead
lab study, simulation-based

296 million spins on book of dead: 11 of 12 casinos run a version that busts bankrolls faster

exp · 004 · 2026-06-12 · simulation-based

provider Play'n GORTP 96.21% (versions: 96.21*;94.25;91.25;87.25;84.18)volatility high
at 50c a spin
€2,500
biggest win
5,000x top win
€41
average bonus
when it hits (81x)
€0.48
avg back per spin
of your 50c
win hit frequency 26.2% (~1 in 3.8 spins)max win 5,000x = €2,500 (a feature event)
we simulated 296,148,201 spins of book of dead across three rtp configurations: the 96.21% provider default that every review quotes, the 94.25% version that 9 of 12 casinos in FindMyRTP's june 2026 scan actually run, and the 87.25% floor observed live at one of them. at $0.50 a spin against a $100 bankroll, 73.6% of sessions busted on the default, 75.3% on the modal deployed version, and 84.0% on the floor. the version you sit down at matters more than anything you do after you sit down.

Run it yourself in the live simulator. All figures are simulation-based observations, not predictions. See our methodology.

what we measured

parametervalue
configs simulated96.21% (provider default) · 94.25% (modal deployed) · 87.25% (deployed floor)
known variant ladder96.21 / 94.25 / 91.25 / 87.25 / 84.18, a verified 12.03pp spread
stakes$0.20 / $0.50 / $1.00 per spin
bankrolls$50 / $100 / $200
sessions10,000 per stake/bankroll cell, 90,000 per config, 270,000 total
spin cap2,000 spins per session
play modelflat stake, all 10 lines, optional gamble feature not used

the question this answers: book of dead's published math describes a version most players never see, so how do bankrolls actually behave on the version most casinos deploy, measured against the brochure number?

model inputs worth flagging: play'n go does not publish hit frequency or bonus trigger rate. we used a single community tracker's large-sample estimates (hit 26.16%, free spins 1 in 192.2, average bonus 81.28x, from 8.32M tracked spins), low-confidence inputs, documented as estimates. all three configs share them, so the cross-version deltas below are insensitive to that uncertainty; absolute session-length and bonus-gap figures inherit it.

how long bankrolls survived

survival curves, share of sessions still alive vs spins played

at the $100 bankroll (default config), the stake sets the clock: median session length was 274 spins at $1.00, 788 spins at $0.50, and the full 2,000-spin cap at $0.20. the $1.00 curve falls off a cliff almost immediately, half of those sessions were dead before spin 274, which at real-world pace (~5 spins a minute) is under an hour. the deployed versions compress everything: at $0.50/$100 the median session shrank from 788 spins (default) to 744 (94.25 config) to 584 (87.25 floor).

bust rates

bust-rate grid, share of sessions that busted before the spin cap

bust rates within the 2,000-spin cap, default 96.21 config, 95% CIs:

$50 bankroll$100$200
$0.20/spin65.2% ±0.929.2% ±0.90.3% ±0.1
$0.50/spin86.9% ±0.773.6% ±0.942.7% ±1.0
$1.00/spin94.0% ±0.587.5% ±0.772.5% ±0.9

plain reading: hold the bankroll at $100 and move the stake from $0.20 to $0.50, and the bust rate jumps from 29.2% to 73.6%, the single biggest lever in the grid. the only cell where busting is rare is $0.20 against $200 (0.3%), which is also the cell with 1,000 spins of cover per bankroll. dead streaks were unremarkable for a high-volatility title: the 90th-percentile session's worst winless run was 25 spins at $0.50/$100; the longest observed anywhere in 90,000 default-config sessions was 60 spins (a sample observation, not a distribution claim).

the bonus wait, and what it pays

at the tracker-estimated trigger rate of 1 in 192.2, a model input, and a low-confidence one, our simulated sessions averaged one free-spins round every ~192 spins, as expected. the payout side is where the texture is (model-based estimates; 500,027 simulated bonuses pooled, default config): the average bonus paid 81.2x stake, but the median was 44.4x, half of all bonuses paid less than that. 23.3% paid under 20x, 54.3% under 50x. the top 1% paid 572.7x or more, and the 5,000x cap was reached in sample. that gap between the 81x average and the 44x median is the whole game: the expanding-symbol round carries the math on rare big hits, and the typical round pays well under the average everyone remembers.

a $50 bankroll at $1.00/spin affords 50 spins of cover against a 1-in-192 trigger, most of those sessions (94.0% busted) never saw the feature at all.

what a finished session looks like

final bankroll by percentile

the final-bankroll distribution at $0.50/$100 (default config) is two stories with nothing in between: half of all sessions ended with less than $0.35 of the original $100, and 70% ended below $0.48, busted, in effect. then the distribution jumps: the 80th percentile kept $115.79 and the 90th kept $291.96. book of dead sessions don't drift to a middling result; they either die or detonate upward, which is what a 10-line high-volatility engine with a 5,000x ceiling is built to do.

there is no bonus-buy section in this study: book of dead (2016) has no feature buy, no multipliers, and no ante, the classic engine predates all of it, so there is nothing to measure.

the rtp version lottery

this is the section book of dead was made for. the game ships at 96.21%, and also exists at 94.25, 91.25, 87.25 and 84.18: a fully verified 12.03pp ladder, the widest on our files, across which the house edge more than quadruples (3.79% → 15.82%).

here is the part that isn't theoretical. FindMyRTP's june 2026 scan of 12 casinos found only one running the top setting. nine ran 94.25, one ran 91.25, and one ran the 87.25 floor. eleven of twelve below default, for this title, the published number is the exception, not the rule. a community tracker's realised return of 93.8% over 8.32 million real spins sits almost exactly on that deployment picture. so we didn't just simulate the brochure; we ran the full grid at the deployed versions too. measured deltas, same model, same inputs, only the rtp changed:

cell96.21 default94.25 (9 of 12 casinos)87.25 (deployed floor)
$0.20/$100 bust29.2% ±0.932.9% ±0.9 (+3.7pp ±1.3)47.8% ±1.0 (+18.6pp ±1.3)
$0.50/$100 bust73.6% ±0.975.3% ±0.9 (+1.7pp ±1.2)84.0% ±0.7 (+10.4pp ±1.1)
$0.50/$200 bust42.7% ±1.046.8% ±1.0 (+4.1pp ±1.4)60.6% ±1.0 (+17.9pp ±1.4)
$1.00/$200 bust72.5% ±0.976.0% ±0.8 (+3.5pp ±1.2)84.1% ±0.7 (+11.6pp ±1.1)
$0.20/$200 bust0.3% ±0.10.5% ±0.11.8% ±0.3
median session, $0.50/$100788 spins744 spins584 spins

the modal deployed version raised the bust rate's point estimate in all nine cells, statistically significant in eight of nine (everywhere except $1.00/$50, where sessions die too fast for 2pp of rtp to resolve). the floor raised it in all nine. the safest cell in the grid, $0.20 against $200, saw its bust rate go from 0.3% to 1.8% between the default and the floor: six times as many busted sessions, purely from which version the casino licensed. same game, same symbols, same free spins. the only difference is a setting you can't see.

(the 84.18 floor of the ladder exists in the verified math but has no deployment sighting on file; we did not simulate it.)

methodology note

we simulate models calibrated to published math, rtp, hit frequency, volatility profile, bonus behavior, not the provider's game engine. results are sample-based observations from 296 million simulated spins (270,000 sessions across three rtp configurations), with 95% confidence intervals shown. hit frequency and bonus trigger rate are single-tracker community estimates, used as documented model inputs. slots are negative-expectation games; nothing here predicts outcomes or improves odds. model and validation data: bod-v1 (96.21 target, analytic calibration exact, 10M-spin check measured 96.325% ±0.366pp se), bod-v1@94.25 (measured 94.360% ±0.364pp se), bod-v1@87.25 (measured 87.342% ±0.357pp se), all within tolerance. corrections policy: methodology.html.

Where the max win actually comes from

base 54%
feature 42%

44% of this game's RTP is locked inside the bonus you rarely trigger; the base game on its own returns just 54%.

A normal spin in our simulation never returned more than ~500x (€250). The 5,000x top win is a feature event, it only came out of the bonus. (base-game ceiling: paytable-sourced)

Play the Book of Dead demo, or stress-test it

Looking for the Book of Dead demo or free play? A demo shows you a handful of spins. Our free simulator runs Book of Dead across thousands of sessions and shows what actually happens to a bankroll over time: the bust rate, how long the money lasts, and the wait for the bonus. It is the demo with the math switched on.

stress-test Book of Dead free

FAQ

Is there a Book of Dead demo or free play?

Yes. You can play Book of Dead in demo mode at most casinos, and you can stress-test it free in our simulator, which runs thousands of sessions and reports the bust rate and session length, the demo with the math switched on.

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