Midnight Library slot: RTP and max win
Midnight Library is a medium-volatility slot by RelaxPls on Stake Engine, released 31 Jul 2026. Its base game returns 96.70%, above the median Engine slot (96.02%) and higher than 86% of them. The top payout is 25,000× the bet, bigger than 81% of Engine slots; from a base spin it lands about once every 1,250,001 spins. It has 4 bonus buys priced at 74× to 213× the bet; the best returns 96.70%, so each buy costs 2.44× the bet on average over the long run. It is the No. 4733 most played Engine slot over the last 30 days.
Every mode, side by side
Costs are multiples of the base bet. Odds come from the published outcome table for v1. "Returns the cost" counts rounds that pay back at least what the mode cost. Expected cost is cost × (1 − RTP): the average amount lost per round over the long run.
| Mode | Type | Cost | RTP | Max win | Max win odds | Pays anything | Returns the cost | Expected cost per round | |
|---|---|---|---|---|---|---|---|---|---|
| Base | Base spin | 1.00× | 96.70% | 25,000× | 1 in 1,250,001 | 1 in 3.95 | 1 in 16 | 0.03× base | Simulate |
| Bonus Boost | Boosted spin | 1.50× | 96.70% | 25,000× | 1 in 833,334 | 1 in 3.89 | 1 in 42 | 0.05× base | Simulate |
| Bonus | Bonus buy | 74× | 96.70% | 25,000× | 1 in 16,892 | – | 1 in 7.16 | 2.44× base | Simulate |
| Wild 1000 | Bonus buy | 100× | 96.70% | 25,000× | 1 in 12,500 | 1 in 1.02 | 1 in 9.65 | 3.30× base | Simulate |
| Wild 5000 | Bonus buy | 190× | 96.70% | 25,000× | 1 in 6,579 | every round | 1 in 8.49 | 6.27× base | Simulate |
| Mystery Bonus | Bonus buy | 213× | 96.70% | 25,000× | 1 in 5,869 | – | 1 in 5.04 | 7.03× base | Simulate |
Work out the cost of Midnight Library bonus buys at your bet size
Version history
Base-mode RTP per published math version. Older versions stay public in the fairness API, so changes can be checked.
| Version | Base RTP | |
|---|---|---|
| v1 | 96.700% | Active |
Frequently asked
What is the RTP of Midnight Library?
Base spins return 96.70% of the amount wagered over the long run, from the published outcome table for version 1. All 4 of its bonus buys return 96.70%.
What is the max win in Midnight Library and how likely is it?
The top payout is 25,000× the base bet. On a base spin it lands 1 in 1,250,001 spins. In the Bonus buy (74×) 25,000× lands 1 in 16,892 buys.
Does Midnight Library have a bonus buy, and what does it cost?
Yes, 4 buy modes. Bonus: 74× the base bet, 96.70% RTP, an expected cost of 2.44× the base bet per buy. Wild 1000: 100× the base bet, 96.70% RTP, an expected cost of 3.30× the base bet per buy. Wild 5000: 190× the base bet, 96.70% RTP, an expected cost of 6.27× the base bet per buy. Mystery Bonus: 213× the base bet, 96.70% RTP, an expected cost of 7.03× the base bet per buy.
Is Midnight Library high or low volatility?
Medium. Its base-mode standard deviation is 24.2× the bet, which puts it in the middle third of Engine games. What volatility means.
Can I check that a result was fair?
Yes. Engine games use provably fair seeds. Once your server seed is revealed you can replay any round against the published outcome table. See how to verify a result.
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