Tome of Madness launched on June 27, 2019 and is Play'n GO's Lovecraft/Cthulhu horror slot, starring Rich Wilde as protagonist (an extension of the franchise that began with Book of Dead). It runs a 5x5 Cluster Pays format, an RTP of 96.59% (the top of Play'n GO's portfolio), and a max win of 2,000x.
It's arguably the most creative slot in Play'n GO's portfolio mechanically: Eye Marks, ABYSS and VOID Portal Effects, and a 2x2 Mega Wild Cthulhu that descends through the cascades. This review breaks down every unique mechanic, compares the RTP against the rest of the portfolio, and covers where to play it for real money in 2026.
TL;DR — Tome of Madness in 4 points
- Play'n GO slot, June 2019, Lovecraft/Cthulhu horror theme starring Rich Wilde. 5x5 Cluster Pays format (4+ adjacent symbols to win). RTP 96.59% (degraded versions range 84.50%-94.52% ⚠️).
- High volatility, max win 2,000x.
- Cascading reels + Eye Marks that unlock Special Wilds + a Portal meter (collect 42 symbols to trigger the bonus) + ABYSS Portal Effect (clears a row/column) + VOID (clears a symbol type) + a 2x2 Mega Wild Cthulhu + a Rich Wilde Multiplier Wild (2x payouts).
- No bonus buy.
Tome of Madness mechanics in detail
The 5x5 Cluster Pays format — the foundation
A 5-column by 5-row grid running Cluster Pays: you win when 4 or more identical symbols connect vertically or horizontally on adjacent positions (versus the 3+ threshold on Rise of Olympus). That higher 4+ threshold makes clusters rarer but more rewarding when they land.
Symbols include Lovecraft-flavored icons (books, octopus tentacles, runes), Rich Wilde (multiplier wild), and Cthulhu (the 2x2 mega wild).
Cascading reels with symbol removal
The standard Play'n GO Cluster mechanic:
- Winning symbols disappear after each cluster
- New symbols drop in from above
- Cascades continue as long as wins keep landing
- Difference versus Rise of Olympus: no progressive multiplier on cascades here (offset by the Eye Marks instead)
Eye Marks unlock Special Wilds
This is the signature mechanic animating the base game:
- Certain positions on the grid are marked with Eye Marks (open eyes)
- When a winning cluster lands on a position with an Eye Mark, that mark transforms into a Special Wild
- Special Wilds stay in place through subsequent cascades
- The more clusters you chain, the more the grid fills up with permanent Special Wilds
This is what can turn an average session into a big one — through the accumulation of permanent wilds.
Portal Meter — collect 42 symbols
The progression mechanic toward the bonus:
- Every winning symbol collected feeds a Portal meter
- Once the meter reaches 42 collected symbols, you trigger the Portal bonus
It's a bonus that's slow to unlock, but cumulative across the session.
Portal Effects — ABYSS and VOID
When the Portal triggers, you get a random effect:
| Effect | Mechanic |
|---|---|
| ABYSS | Clears an entire row or column of the grid |
| VOID | Clears an entire symbol type from the grid |
These effects empty out the grid and force major cascades as new symbols drop in. In tested ABYSS/VOID sessions, the average payout ran 80-200x the stake when combined with Special Wilds already in place.
Mega Wild Cthulhu 2x2
The Cthulhu Mega Wild is the most devastating symbol on the reels:
- Lands in a 2x2 format (4 adjacent cells)
- Substitutes for every symbol across those 4 cells
- Descends through the cascades (staying active across multiple spins)
This is the event that can generate 300-500x the stake in a lucky free spins session with Cthulhu well-aligned.
Rich Wilde Multiplier Wild
The Rich Wilde Multiplier Wild is more subtle:
- Substitutes for other symbols
- Doubles the payout of active paylines
- Appears alongside the Special Wilds
96.59% RTP — top of Play'n GO's portfolio
| Play'n GO slot | Official RTP |
|---|---|
| Tome of Madness | 96.59% 🏆 |
| Rise of Olympus | 96.5% |
| Book of Dead | 96.21% |
| Fire Joker | 96.15% |
| Hugo 2 | 94.56% |
| Annihilator | 94.2% |
⚠️ Watch out for degraded versions:
- Official: 96.59% ✅
- Mid: 94.52%
- Low: 91.59%
- Lower: 87.52%
- Lowest: 84.50% ⚠️
Check via the in-game "i" button.
Tome of Madness strategy
At 96.59% RTP and high volatility, here's what we recommend:
- Flat bet €0.20-€0.50 across 200-300 spins
- Target the Portal bonus: roughly 1 trigger per 100-150 spins (collecting 42 symbols)
- Eye Marks: present from the base game, triggering Special Wilds regularly
- Cthulhu Mega Wild: fairly rare (roughly 3-5 per 1,000 spins) — accept it as a bonus event
- Bankroll target: 60-80x your stake (high volatility, but not extreme)
Top 5 casinos to play Tome of Madness in 2026
🟢 1. SpinAura — Our #1 pick, 9.2/10
A full Play'n GO catalog with the confirmed 96.59% RTP. 100% bonus up to €15,000 + 24-hour withdrawals.
💎 2. BetRiviera — 8-minute withdrawals
Confirmed Play'n GO catalog, with an 8-minute withdrawal record in the space.
🎰 3. MonacoJack — Premium pick
A full Play'n GO catalog.
🔵 4. BigClash — Casino + sportsbook
A hybrid platform with Play'n GO on board.
🔴 5. Betti — 150% bonus + 150 free spins
150% bonus up to €1,500 + 150 free spins, with accessible wagering.
FAQ — Tome of Madness
What is Tome of Madness's RTP?
Official RTP: 96.59% — the highest in Play'n GO's portfolio. ⚠️ COMMON degraded versions: 94.52% / 91.59% / 87.52% / 84.50%. Check via the in-game "i" button. At SpinAura and BetRiviera, the 96.59% version is confirmed.
What's the maximum win on Tome of Madness?
2,000x your stake per session. At a €0.10 stake (minimum), the theoretical max win is €200. At €100 (maximum), the max win is €200,000. That's modest compared to Play'n GO's more modern portfolio (Book of Dead at 5,000x, Rise of Olympus at 5,000x). It's the slot's main weakness relative to its chart-topping RTP.
Is Tome of Madness widely available?
Yes, at most crypto/anonymous casinos in our top rankings that carry Play'n GO.
Is a bonus buy available?
No. Tome of Madness has no bonus buy — the Portal bonus only triggers via the 42-symbol collection. That's consistent with Play'n GO's policy in 2019.
How exactly do the ABYSS and VOID Portal Effects work?
Once the Portal meter hits 42 collected symbols, the bonus triggers with a random effect:
- ABYSS clears an entire row or column (5 cells), forcing new cascades
- VOID clears an entire symbol type (every occurrence) — potentially freeing up 6-10 cells
The newly emptied cells refill through cascades, which can generate massive combos if Special Wilds are already in place.
Tome of Madness or Rise of Olympus?
Tome of Madness: a marginally higher RTP (96.59% versus 96.5%), the Mega Cthulhu 2x2, an innovative Portal mechanic, but a max win of only 2,000x. Rise of Olympus: 3 distinct free spin modes, a 5,000x max win (2.5x higher), and a harsher 10/10 volatility. For big-win hunters: Rise of Olympus. For those chasing the top RTP with creative mechanics: Tome of Madness.
What's the best strategy?
Flat bet €0.20-€0.50 across 200-300 spins. The slot rewards patience on the Portal meter (42 symbols to collect). Eye Marks and Special Wilds keep engagement up between Portal bonuses. If you've had 0 Portal bonuses after 250 spins, switch slots.
How much bankroll do you need to play Tome of Madness well?
A minimum of 60 times your stake. At €0.10, that's a minimum bankroll of €6. At €0.50, minimum €30. High volatility but not extreme — more accessible than Rise of Olympus (10/10).
Go further
- ⛰️ Rise of Olympus review — Play'n GO's Greek Cluster Pays (96.5% RTP)
- 📕 Book of Dead review — THE #1 Play'n GO slot
- 👽 Reactoonz review — Play'n GO's alien Cluster Pays
- 💡 Which slot pays the best in 2026 — The complete RTP pillar
- 💙 Full SpinAura review — The market benchmark
🎰 Tome of Madness slot page for the full technical breakdown.
Casinos recommandés par nos experts
Les plateformes ci-dessous proposent des bonus avec des conditions claires et un suivi vérifié par notre équipe.
