Quick verdict: Diamond Mine Megaways is Blueprint Gaming's 2018 licensed take on the Megaways format, taking its original fixed-reel Diamond Mine slot and rebuilding it on Big Time Gaming's engine for up to 117,649 ways to win. A TNT Mystery Barrel adds a wild-reveal mechanic to the base game, while Strike Gold — the colossal bonus round with an unlimited increasing multiplier — is where the game's real potential sits. At up to 96.43% RTP and rated 5 out of 5 on Blueprint's own volatility scale, this is one of the studio's higher-variance Megaways titles.
The Story
Blueprint Gaming released Diamond Mine Megaways in May 2018, licensing Big Time Gaming's Megaways engine to rebuild its earlier fixed-reel Diamond Mine slot around a variable-ways grid. The theme is straightforward and unpretentious — a gold rush-era mine setting with TNT, pickaxes and glittering diamonds — built to carry the mechanic rather than tell a story. It's part of a small family of Diamond Mine titles Blueprint has released over the years, with this Megaways version standing out as the highest-volatility entry, rated at the very top of the studio's own risk scale.
Theme, Gameplay & Symbols
Diamond Mine Megaways runs on Big Time Gaming's Megaways engine, offering up to 117,649 ways to win on a variable-height reel set. Low-paying symbols are the standard playing-card royals; higher-paying symbols pull from the mining theme, building toward diamond-value symbols at the top of the pay table. Wins cascade, removing winning symbols and dropping new ones into place for the chance at further wins from the same spin at no extra cost.
Presentation & Sound
Visually, Diamond Mine Megaways keeps things simple and functional — a rocky mine-shaft frame around the reels, warm gold-and-earth tones throughout, and clean, legible symbol art that doesn't overcomplicate what's ultimately a Megaways cascader. It's a 2018-era production, so don't expect the layered animation of Blueprint's more recent releases, but the presentation does its job without getting in the way of tracking cascades and the TNT Mystery Barrel. The soundtrack is an upbeat mining-themed loop, with a distinct rumbling sound effect whenever the TNT Barrel triggers and a more dramatic sting marking the start of the Strike Gold bonus round.
How to Play Diamond Mine Megaways
- Set your stake using the bet selector. Blueprint Gaming's own published range runs from £0.20 to £100 per spin, though exact limits can vary by operator — and UKGC rules cap UK online slot stakes at £5 per spin (£2 for 18–24-year-olds), so UK players can't stake anywhere near the top of that range.
- Spin the grid. Wins pay across up to 117,649 ways when matching symbols land on adjacent reels starting from the leftmost reel.
- Watch for cascades: winning symbols clear and new ones drop in, with any further win from the same spin paying at no extra cost.
- Watch for the TNT Mystery Barrel — it can reveal as any other symbol on the grid, opening up more ways to complete a winning combination.
- Land 4 Bonus symbols to trigger Strike Gold, the colossal bonus round.
- Inside Strike Gold, an unlimited increasing multiplier applies to every win, climbing further with each hit for the rest of the round.
Features & Mechanics
The TNT Mystery Barrel is Diamond Mine Megaways' signature base-game mechanic: when it lands, it can reveal as any other paying symbol on the grid, effectively acting as a wildcard that opens up additional ways to complete a winning combination on that spin. Combined with the cascade mechanic, a well-placed TNT Barrel reveal can chain into further wins as the grid refills.
Landing 4 Bonus symbols triggers Strike Gold, Blueprint's name for the game's main bonus round. Once inside, every win applies to an unlimited increasing multiplier that climbs with each hit for the remainder of the round — Blueprint's own promotional material describes it plainly as an "unlimited increasing multiplier on every win," with no published cap on how high it can climb within a single round.
Volatility & Win Potential
Blueprint Gaming publishes three RTP configurations for Diamond Mine Megaways — reduced builds at 92.01% and 93%, and a top figure of 96.43% — so it's worth checking the in-game info screen at whichever operator you play, since which build is live depends entirely on the operator. Blueprint rates the game at 5 out of 5 on its own volatility scale, the maximum rating the studio uses, putting it among the highest-variance titles in Blueprint's Megaways catalogue. Blueprint doesn't publish a specific max win or hit-frequency figure for this title, so we won't put a number on either — treat the 5/5 rating as the clearest signal that long dry spells between meaningful wins are the norm here.
Pros & Cons
- Pro: The TNT Mystery Barrel gives the base game a genuine wildcard mechanic that can chain into further cascades.
- Pro: Strike Gold's unlimited increasing multiplier means a strong run inside the bonus round has no published ceiling on how far it can climb.
- Pro: Up to 117,649 ways to win on a well-established, proven Megaways foundation.
- Con: Rated 5 out of 5 on Blueprint's volatility scale — the maximum rating — so long, difficult stretches between bonus triggers are the norm, not the exception.
- Con: No published max win or hit-frequency figure from Blueprint, so some of the game's win potential can't be pinned down precisely.
- Con: A 2018-era production — presentation is functional rather than visually ambitious next to Blueprint's newer Megaways releases.
Final Verdict
Diamond Mine Megaways earns its place among Blueprint's higher-variance Megaways titles through a straightforward but effective combination: a TNT Mystery Barrel that adds genuine unpredictability to the base game, and a Strike Gold bonus round with an uncapped increasing multiplier that rewards patience with real upside. At up to 96.43% RTP and the maximum 5/5 volatility rating, it's built specifically for players who want the highest end of Blueprint's risk spectrum rather than a gentler, more frequent-win experience. Worth trying via the free demo below to see how the TNT Barrel and Strike Gold multiplier play out before wagering anything for real.
