Nitropolis 4 (ELK Studios) – Review & Demo Play

Nitropolis 4 Slot Overview

Nitropolis 4 from ELK Studios takes the nitro gangs offshore, shifting the action to rigs and seabed runs. It plays on 6 reels with 4 to 8 rows, starting at 4,096 ways and expanding via Avalanches. Wins remove symbols, add a row, and can push the grid to its 8-row peak. The maths sits on the spicy side with high volatility and a fixed 94% RTP. The payout ceiling is 50,000x stake, which keeps the series’ headline potential intact. Both Ways can come into play through features, adding extra paths when the setup opens up.

Stakes range between £0.20 and £50 per spin, and the feature roster is loaded. Wilds sub in for pays, Big Symbols land as 2x2 or 3x3 blocks, and Nitro Reels stack symbols in two-cell strips, with Big Nitro Reels covering six positions. Nitro Multipliers appear with x4 to x12 values. Above the grid, Nitro Booster monitors can throw in modifiers. Bonus spins and the X-iter options round out a package built for momentum and punchy turns.

Symbols and Paytable in Nitropolis 4

Royals J to A are the lower pays, topping out at 0.3x for six of a kind. Mid-tier comes from the gang emblems for Rogue Rats, Pug Thugs, Gritty Kitties, and Dirty Dawgs, paying 0.8x to 1x for six. The four leaders are the premiums, landing 1.25x to 3x for a full line. The naval mine Wild substitutes and also pays up to 3x. Bonus scatters are the hand-cranked submarines, with a Super version that upgrades the bonus.

Nitropolis 4 Symbols and Paytable

Symbol	Quantity	Payout
	6	x3
	5	x2.5
	4	x2
	3	x1.5
	6	x2
	5	x1.5
	4	x1.25
	3	x1
	6	x1.5
	5	x1.25
	4	x1
	3	x0.75
	6	x1.25
	5	x1
	4	x0.75
	3	x0.5
	6	x1
	5	x0.5
	4	x0.3
	3	x0.2
	6	x1
	5	x0.5
	4	x0.3
	3	x0.2
	6	x0.8
	5	x0.4
	4	x0.25
	3	x0.15
	6	x0.8
	5	x0.4
	4	x0.25
	3	x0.15
	6	x0.3
	5	x0.2
	4	x0.15
	3	x0.10
	6	x0.3
	5	x0.2
	4	x0.15
	3	x0.1
	6	x0.3
	5	x0.2
	4	x0.15
	3	x0.1
	6	x0.3
	5	x0.2
	4	x0.15
	3	x0.1
	Scatter
	Wild

Core Mechanics in Nitropolis 4

Avalanches trigger on every win. Contributing symbols vanish, new ones drop, and the grid grows by one row per chain up to 8 high. As the rows climb, ways rise from 4,096 towards huge counts, which is where the slot starts to breathe. If Nitro Reels or Nitro Multipliers help a win, they award a respin within the sequence, keeping the pace up while the tally builds for as long as hits keep landing.

Big Symbols appear at random in 2x2 and 3x3 sizes, counting as the relevant number of 1x1 tiles and covering lows, mids, highs, or even Wilds. Nitro Reels occupy two positions and carry 4, 6, 8, 10, or 12 regular symbols, while Big Nitro Reels fill six positions with 2 to 6 stacked 2x2 symbols. These containers can also hold Super scatters, though each counts as a single scatter for entry purposes when housed in a Nitro Reel.

Nitro Booster and Multipliers in Nitropolis 4

The twin Nitro Booster screens above the grid can light up with eight modifiers: Both Ways, Redrop, Max Rows, Garbage Collect, Nitro Appear, Nitro Wild, Nitro Upgrade, and Nitro Match. They tweak layout, seed or tune Nitro Reels, or clear space to set up hits. Nitro Multipliers cover two cells and apply x4, x6, x8, x10, or x12 to wins in view. Multiple multipliers multiply together, which is where the largest sequences pick up pace.

Free Spins and X-iter in Nitropolis 4

Hit three to six Bonus scatters to trigger 8, 12, 16, or 20 free spins. During the round, any Nitro Reel that lands turns sticky until the feature ends. Each winning spin raises a safety level by one row, so subsequent spins start at the saved height. Retriggers are possible on extra scatters. Land at least one Super scatter to launch the Super Bonus, where Both Ways and Max Rows sit active from the start for a wider field and sharper lines.

The free spins tempo differs from base play. Sticky Nitro Reels hold lanes open, Nitro Matches can stitch wins, and Multipliers can stack in view. When the safety level climbs, the 8-row cap comes into reach, and ways increase accordingly. This is where the slot’s long chains tend to form, helped by Redrops and upgrades that keep the reels primed. It’s volatile, but when it rolls, the board can turn into a conveyor of linked outcomes.

X-iter gives five paid modes. 2x stake raises the chance to trigger the bonus. 10x stake fires a spin where Nitro Booster delivers two modifiers. 25x stake buys a Super Spin with Max Rows and Both Ways active. 100x stake buys the standard Bonus Game. 500x stake buys the Super Bonus. It’s a tidy menu for direct access, mirroring the options listed in the series, and it suits players who prefer to target the feature set straight away.

Bets, RTP and Variance in Nitropolis 4

The bet spread sits at £0.20 to £50 per spin, which covers casual sessions and higher stakes. The published RTP is 94%, a fixed figure for this release, and sits below the typical mid-ninety band. Variance is high, so stretches of modest returns can appear, followed by stronger bursts when modifiers and row growth align. That profile fits the series ethos: fewer safe taps, more punch when the grid opens and multipliers link with premium symbols.

The max win lands at 50,000x stake. With the grid at 8 rows and Both Ways in play, the ways count can reach into the millions, though it’s the right blend of Nitro Reels, Big Symbols, and Nitro Multipliers that really shifts outcomes. I manage stake by nudging bets when modifiers appear more frequently, then dialling back during quieter spells. It’s a slot that rewards patience and clear limits, rather than constant bet hopping.

Play Experience & First Impressions in Nitropolis 4

Flashy sums it up. During a 100-spin test, the soundtrack, callouts, and shifting rows kept me engaged, though the pace can feel full-on. Modifiers popped roughly every third or fourth spin for me. Base hits weren’t frequent, but when Nitro Multipliers landed with Big Symbols or a Match, the numbers stood out. I didn’t reach free spins in that set, but earlier sessions did, and the sticky reels made a clear difference. High octane, swingy, and worth a session.