Space Miners Slot Review

Space Miners by Relax Gaming blasts you into an asteroid mining operation across a 6x4 grid with 466 ways to win. Released in 2021, this high-volatility slot packs expanding reels, cluster pays, multipliers, and a max win of 15,000x your stake. Before you commit real cash, try the free demo above to see if this deep-space grind suits your style.

Space Miners isn't a slot that showers you with frequent wins and cheerful jingles. It's a cold, unforgiving vacuum punctuated by massive explosions of value. If you need constant dopamine hits from your base game, close this tab now. This one demands patience and a bankroll that can absorb long stretches of nothing.

Think of it as sitting somewhere between Relax Gaming's own Money Train 2 in terms of bonus intensity and Reactoonz by Play'n GO in terms of its grid-based cluster mechanics. Space Miners carves its own identity with the expanding reel system — the grid literally grows during the bonus, opening up more ways to win when you need them most. It's a clever design choice that makes the feature round feel genuinely different from the base game.

The base game runs on a 6x4 grid using 466 ways to win. Symbols connect in clusters, and wilds substitute to help complete combinations. The real math here lives in the expanding reels mechanic: during free spins, the grid can grow up to 6x8, pushing the ways-to-win count dramatically higher.

Multipliers stack during the bonus round, and that's where the 15,000x max win lives. In practice, a session feels like a slow burn. You'll watch your balance tick down steadily — maybe losing 30-40% before anything meaningful lands. Then a single bonus round can flip everything. We tested over 500 spins across multiple sessions, and the variance was extreme. One session returned 3x our starting balance; another ate through 200 spins without triggering the feature once.

The RTP sits at a healthy 96.5% (house edge of 3.5%), which is above average for a high-volatility slot. That said, RTP is a long-term theoretical number — your 100-spin session will look nothing like it.

Three or more scatter symbols trigger the free spins bonus. You start with a set number of free spins, and here's where it gets interesting: every winning combination during the round can expand the reel set. Rows are added to the grid, increasing from the standard 4-row layout up to 8 rows. More rows means exponentially more winning ways.

Multipliers also accumulate during the feature. Each retrigger or expansion step adds to your multiplier value, and these multiply your total win at the end of the round.

In our testing, the bonus triggered roughly every 150-200 spins on average. That's on the slower side. When it does hit, payouts ranged wildly — from a disappointing 15x (yes, that happens) to a session-saving 800x. The truly massive wins north of 5,000x require full reel expansion plus high multipliers, which is a rare alignment. But at 15,000x max, the ceiling is real.

Play if:

• You have at least 300-500x your bet size in bankroll (€60-€100 at minimum bet)
• You enjoy high-volatility slots where a single bonus can define your session
• You appreciate mechanical innovation — the expanding reels genuinely change the math mid-feature
• You're playing at one of the best slots sites with a solid welcome bonus to extend your runway

Skip if:

• Your bankroll is under €30 — this slot will eat it before you see a feature
• You prefer frequent small wins and steady entertainment value
• Long dry spells frustrate you (150+ spins between bonuses is normal)
• You're prone to chasing losses — read up on casino bonus mistakes before playing anything this volatile

Space Miners is widely available at Relax Gaming partner casinos. UK players can find it at licensed operators offering the full Relax Gaming portfolio. We recommend choosing fast payout casinos so that when you do land a big feature win, your withdrawal isn't stuck in processing limbo for days.

Space Miners is a feast-or-famine slot that demands respect for your bankroll and rewards genuine patience. The expanding reel mechanic during free spins is genuinely innovative, and 15,000x max win gives it real big-hit potential. But those long base-game droughts are brutal. If you can handle the grind, this is one of Relax Gaming's more underrated releases. If you can't, your balance will evaporate before you ever see the grid expand.

Key Stats

• Provider: Relax Gaming
• RTP: 96.5%
• Volatility: High
• Max Win: 15,000x
• Reels: 6x4 (expanding to 6x8)
• Ways to Win: 466
• Bet Range: €0.20 – €20
• Features: Wilds, Free Spins, Expanding Reels, Cluster Pays, Multiplier

Responsible Gambling

High-volatility slots like Space Miners can produce extended losing streaks. Never bet more than you can afford to lose. Set deposit limits, time limits, and use self-exclusion tools if needed. Read our responsible gambling guide and visit BeGambleAware.org for independent support and resources.