Merlin's Grimoire Slot Overview
Play'n GO released Merlin's Grimoire on 7 July 2022 as the fourth Merlin-themed entry in its Arthurian catalogue, joining Rise of Merlin, Merlin and the Ice Queen Morgana, and Lord Merlin and The Lady of the Lake. The grid is a 5-reel, 3-row layout, ivy-covered and set in stone, framed by a dense forest backdrop.
What sets this one apart from the studio's previous Merlin titles is the combination of expanding symbols from the 'book of' template with splitting symbols borrowed from the Gems range. Default ways start at 243 and can climb to 7,776 in Free Spins. It is a more mechanically ambitious entry, even if the theme treads familiar ground.
Symbols and Paytable
Six esoteric tokens in green, blue, purple, orange, red and yellow handle the low end, paying 0.8x to 1x the bet for five of a kind. The high tier is made up of a scroll, a blue potion, a staff and Merlin himself, returning between 2.5x and 4x the bet for a five-of-a-kind line.
The Grimoire book covers both wild and scatter duties. As the wild it substitutes for any regular pay symbol; as the scatter it pays 0.8x, 1.6x or 4x the stake for 3, 4 or 5 in view. Wins form from at least two highs or three lows on adjacent reels starting from the leftmost column.
Symbol Payouts
Bonus Features
Splitting Symbols can fire on any base game spin, but only on reels 2, 3 or 4. When a reel activates, every symbol on it duplicates, doubling the row count for that column. With all three middle reels active, ways climb from 243 to 1,944.
Three or more Grimoire scatters trigger 10 Free Spins. Before the round starts, one pay symbol is randomly chosen as the special Expanding Symbol. If it contributes to a win, it covers all positions on its reel and pays from any spot, ignoring adjacency. The retrigger lands extra free spins and can fire up to five times.
Crucially, all five reels can split during Free Spins, not just the central three. That is what unlocks the 7,776-way ceiling. The sweet spot is an expanding symbol firing on a reel that also splits, a stacking event responsible for the game's biggest hits.
Bonus Buy Options
On any base game spin, reels 2, 3 or 4 can activate and split symbols on those reels into two, increasing ways to win up to 1,944.
Landing 3, 4 or 5 Grimoire scatters awards 10 free spins with payouts of 0.8x, 1.6x or 4x the stake. One pay symbol is randomly chosen as the expanding symbol before the round begins.
Active throughout free spins, the chosen symbol expands to cover the whole reel and pays from any position, no adjacency required.
RTP, Volatility and Max Win
The default RTP sits at 96.20%, which is acceptable but not exceptional. Operators can deploy lower configurations of 94.20%, 91.20%, 87.20% or even 84.20%, so checking the in-game info panel before staking real money matters here. The gap between the top and bottom version is significant, and not every casino is upfront about which one it serves.
Volatility is high. Bet range runs from 0.10 to 100 per spin across all devices. Most reviews quote a max win of 30,000x the bet, although some sources cite 31,104x; either way, that ceiling is roughly six times what you get from Book of Dead and exceptional for the 'book of' category. Reaching it requires the expanding symbol to coincide with maximum splits across all five reels in free spins, which is mathematically rare.
