Space Stacks: Slot Overview

In any field, pushing limits usually requires a bit of nerve, and one developer that’s shown the kind of boldness needed to rattle the gambling world is Push Gaming. A look back through its catalogue reveals several online slots that helped reshape expectations. That same inventive mindset drives another release with the fitting name Space Stacks, delivering a reel-based experience that feels genuinely different. The twist comes from a mechanic called Reelbets, which allows players to wager on individual reels for the chance to land different prizes or trigger features depending on the reel chosen. If you’re up for something most players won’t have tried before, it’s time to jump in.

If you’re going to build a truly out-there game, setting it in deep space makes perfect sense—after all, the universe is still packed with unanswered questions. Here’s one: even if the Big Bang did happen, our best scientists still can’t say why it happened. Maybe it’s better left unknown. Or picture it as a cosmic slip-up—some advanced being drops a beaker of experimental goo, panics about getting in trouble, pokes a hole in reality, nudges the mess through with a toe, and it eventually festers into the three-dimensional world we’re stuck in.

So, how does Space Stacks work? To start with, the base game uses 10 reels, where 7 pay Instant Prizes and the remaining 3 are tied to bonus games. It’s somewhat reminiscent of roulette: players pick the size of the bet they want by selecting chips, then clicking the reels they would like to bet on. The first six Instant Prize Block reels begin with bet multiplier values of 2, 2, 3, 5, 10, and 50, while the three Bonus Block reels are Astro, Flip, and Apex. The Max Block offers an Instant Prize of 5,000x. Players can place wagers on as many reels as they like, with a minimum stake of 0.01 credits across all options – max bets range from 10 to 100 credits depending on the reel.

After bets are locked in, hitting the spin button kicks off the round. First, there’s a possibility that the first six Instant Prize values get increased by the Enhancement feature. This may add values of +2 to +1,000 or activate multipliers of x2 to x100. Next, symbols and blocker tiles begin dropping onto the reels. Symbols settle at the bottom, while blocker tiles are cleared away. This dropping process continues until one or more of the reels are filled with 10 active symbols. If a player has wagered on the reel (or reels) that fill up, they win the respective prize.

Space Stacks: Slot Features

If players place bets on the Astro, Flip, or Apex reels and land a win, the matching bonus game activates.

• Astro – Astro launches an Instant Prize wheel made up of 32 segments. The wheel includes Instant Prizes from +2 to +1,000, multipliers from x2 to x100, plus a Collect segment. Players keep gathering Instant Prizes and multipliers until the wheel stops on the collect segment.
• Flip –  A 6×6-sized board appears, and players choose 3 face-down tiles. Each selected tile reveals either an Instant Prize of 1x to 1,000x or a Rocket Symbol. The first Rocket Symbol turns on an x2 multiplier, and every Rocket after that boosts the total win multiplier further. Available win multipliers are x2, x5, x10, or x100. When a Rocket is chosen, it doesn’t reduce the number of picks left.
• Apex – Apex follows the base game concept, but with a handful of rule changes. Here, there are six Instant Prize reels with starting values of 2, 3, 5, 7, 10, and 20. The Enhancement feature applies with possible enhancements of x2 to x20. Once a column fills, its prize is collected. When a second column fills, its prize multiplies the prize already collected. Each Instant Prize won multiplies the already collected prize. After 2 columns have been filled, the game awards three lives. Landing one or more symbols restores the life count to 3. If no symbols land, one life is lost, and when all lives are used up, the feature ends. Alternatively, the feature ends when all columns are filled. The final win is multiplied by the bet on the Feature Block, shown on-screen during the feature.

Space Stacks: Slot Verdict

Push Gaming clearly aimed to break away from the usual formula with Space Stacks, and it succeeds in doing exactly that. Whenever a game strays this far from the standard approach—whether it’s Space Stacks, Pragmatic Play’s Spaceman, or much of what Crazy Tooth Studio has produced—it’s naturally not going to suit everyone. It may take several spins, or rounds, to fully understand what Space Stacks is going for and decide whether it clicks for you. It has a bit of a Dream Drop Jackpot feel in places, only with more layered gameplay and a smaller potential ceiling. The maximum payout here is 5,000x the bet.

Another element that demands more planning than normal is the wagering itself. This isn’t simply about choosing a stake and hammering spin. Do you focus on the lower Instant Prizes, throw a cheeky one-cent bet on the Max just for fun, concentrate on one or two feature reels, or take a completely different approach? It’s up to you, and Push Gaming provides plenty of detail to help players decide. While the overall RTP is 96.23% and volatility sits in the medium range, the paytable also shows return values for each of the ten columns along with the average payout. Useful. Hit frequency would have been useful too, though perhaps that’s a step too far. Still, there’s enough here for players who like to dig into the stats and compare the numbers.

All in all, if you want something other than matching fruit, chasing money symbols, or wandering through yet another exotic Earth-based setting, Push Gaming’s Space Stacks could be exactly the change of pace you’re after. Or it might not be—but having alternatives is never a bad thing. A couple of the bonus games feel fairly familiar at their core, yet overall Space Stacks is undeniably unconventional, making it well worth checking out.