Tome of Madness

Q: What is the RTP of Tome of Madness?

The official RTP is 96.59%. Reduced versions are common at some casinos: 94.52% / 91.59% / 87.52% / 84.50%. Check via the in-game 'i' info button before you play.

8.8/10

Release June 2019· Updated October 2026

A Lovecraftian horror slot by Play'n GO (June 2019). Cluster Pays plus Mega Wild Cthulhu 2x2, max win 2,000x. BetsRank rating: 8.8/10.

RTP

96.59%

Volatility

High

Max Win

2 000x

Grid

5x5 grid

Bonus Buy

Cluster Pays (4+ adjacent symbols)Cascading reels with symbol removalEye Marks unlock Special WildsPortal meter (42 symbols collected)Portal Effects ABYSS (retire row/column) + VOID (retire symbol type)Mega Wild Cthulhu 2x2 (descends with cascades)Multiplier Wild Rich Wilde (double payouts)

Play the free demoOfficial Play'n GO demo · no signup, no real money

8.8

BetsRank Verdict

Our read of the game, based on the data the studio publishes

Released on June 27, 2019, Tome of Madness is the Lovecraftian Cthulhu horror slot from Play'n GO, with Rich Wilde as the protagonist (an extended franchise). Format 5x5 Cluster Pays (4+ adjacent symbols), RTP 96.59% (reduced versions of 94.52% / 91.59% / 87.52% / 84.50% exist — check before playing), high volatility, max win 2,000x. Signature mechanics: cascading reels, Eye Marks that unlock Special Wilds when winning clusters land on them, a Portal meter (collecting 42 symbols triggers the bonus), Portal Effects ABYSS (clears an entire row/column) and VOID (clears a symbol type), a Mega Wild Cthulhu 2x2 that descends with each cascade, and a Multiplier Wild Rich Wilde that doubles payouts. No bonus buy.

Strengths

+RTP of 96.59% is near the top of the Play'n GO portfolio
+A hybrid of Cluster Pays and cascading mechanics
+The Mega Wild Cthulhu 2x2 adds real base-game excitement
+A distinctive Lovecraftian narrative universe
+The Portal mechanic is a genuinely creative bonus system

To consider

−Reduced RTP versions are common in the wild (down to 84.50%)
−Max win of 2,000x is on the low side for a high-volatility slot
−No bonus buy option
−The horror theme may not appeal to every player

About Tome of Madness

Released on June 27, 2019, Tome of Madness is the Lovecraftian Cthulhu horror slot from Play'n GO, featuring Rich Wilde as the protagonist (part of an extended franchise). Format 5x5 Cluster Pays (4+ adjacent symbols, vertically or horizontally), RTP 96.59% (reduced versions of 94.52% / 91.59% / 87.52% / 84.50% are common at some casinos, so it's worth checking before you play), high volatility, max win 2,000x. Signature mechanics include cascading reels with symbol removal, Eye Marks that unlock Special Wilds when a winning cluster lands on their position, a Portal meter that fills up (collecting 42 symbols triggers the bonus), Portal Effects with ABYSS (clears an entire row or column) and VOID (clears an entire symbol type), a Mega Wild Cthulhu 2x2 that descends with the cascades, and a Multiplier Wild Rich Wilde that doubles payouts. There is no bonus buy option.

Key mechanics

▸5x5 Cluster Pays format
▸Cascading reels with symbol removal
▸Eye Marks unlock Special Wilds
▸Portal meter (42 symbols triggers the bonus)
▸Portal Effects ABYSS + VOID
▸Mega Wild Cthulhu 2x2
▸Multiplier Wild Rich Wilde (x2 payouts)

❓Tome of Madness FAQ

What is the RTP of Tome of Madness?▾

The official RTP is 96.

59%. Reduced versions are common at some casinos: 94. 52% / 91. 59% / 87. 52% / 84. 50%. Check via the in-game 'i' info button before you play.

What is the Portal meter?▾

The Portal meter fills up as symbols are collected during play; once 42 symbols are gathered, it triggers a bonus feature carrying either the ABYSS or VOID Portal Effect.

What is the Mega Wild Cthulhu?▾

A 2x2 wild symbol that can appear and descends further down the grid with each cascade, adding to winning combinations along the way.

Is there a bonus buy option?▾

No, Tome of Madness does not offer a bonus buy — the Portal bonus must be triggered naturally by collecting symbols during play.