Nitropolis 4 by ELK Studios - Online Slot Review

The quest for finding an infinite supply of Nitro goes on as we revisit the four factions of the post-apocalyptic adventure in the fourth part of the series. After a long-deserved break in the tropical waters overflowing with toxic waste, they pack up their gear and settle on a desolate oil rig that apparently sits on a massive source of the potent liquid. Being jammed in a small place like that will surely fuel countless conflicts between rats, cats, and dogs, so they'll need to try extra hard to make it work. Luckily, each group has its own unique skills, which will come in handy when distributing the tasks.

We're quite sure that there isn't a slot saga that has reached a formal fourth part. If you know one, please let us know in the comments. Most of the series subdue to the "third time's the charm" rule, but ELK Studios doesn't seem to care much for the stereotypes and powers onward with another installment. And it's not like they're just pushing on for the sake of it, milking the exciting IP they've created. Oh no. As usual, everything sticks to the story, there are clear, logical changes in the art, and the growth of features feels progressively accurate. One would think that in the case of a complex game like Nitropolis and its two sequels, it would be impossible to create a consistent and balanced fourth part. The Swedish studio is one of those teams that don't include such a word in their dictionary and are always eager to take up the challenge.

How To Win On Nitropolis 4 Slot - Features & Mechanics

The base game always starts from a 6x4 setup with a ways win evaluation, including 4,096 possibilities. Every successful hit removes the winning symbols, triggering an avalanche (or cascade) that drops the remaining images to the bottom and completes the view with extra ones. Additionally, every score increases the playing area's size by 1 row, up to 8 total. Due to an insanely high number of potential ways, standard payouts may feel stingy, awarding from 0.1 times the bet for the lowest hits up to 3 times the bet on the 6-of-a-kind sequences of the top Dirty Dawg. However, it's important to note that most wins will consist of multiple ways, making the total prizes at the end of the spin much more significant. A traditional Wild symbol will help connect winning combinations, and you'll also benefit from Big Symbols that may appear in a 2x2 or 3x3 size.

Nitro Reels & Nitro Multiplier

The famous Nitro Reels naturally make an appearance. Their function is identical as in the third installment, providing an opportunity to get up to 12 regular-sized symbols in a single 1x2 instance or 6 2x2 symbols in a 2x2-sized box. All Nitro Reels remain in view on successive cascades, plus they upgrade the number of ways and respin to display a different image after contributing to a win.

Nitro Multipliers land in the same 1x2 form, but they display a number instead of a paying icon. The value will multiply all wins in view on the current spin by x4, x6, x8, x10, or x12. After being used, the Nitro Multiplier area will respin and raffle a random regular symbol or a multiplier value again.

Nitro Booster

An array of supporting features has not been forgotten, although it comes in a slightly different form than in previous parts. Instead of landing the special symbols on the reels, we have two screens on top of the main grid that may display the feature's name after each avalanche. Most of the functionalities will feel familiar if you're accustomed to the series:

• Redrop clears the grid of all regular symbols and populates it with a fresh set.
• Both ways activates payouts also starting from the right side of the screen.
• Max rows expands the playing area up to the maximum 8 rows.
• Garbage collect removes all instances of a selected symbol in view.
• Nitro appear places a Nitro Reel (1x2 or 2x2) in a random position.
• Nitro wild transforms symbols in an existing Nitro Reel in view into Wilds.
• Nitro upgrade increases the number of images in a selected Nitro Reel in view.
• Nitro match transforms symbols in an existing Nitro Reel in view into a different matching symbol.

Nitropolis 4 Bonus Game

Landing 3, 4, 5, or 6 Bonus symbols activates 8, 12, 16, or 20 free spins. The safety levels hold the increased rows, not resetting them to the default 4 after every spin. Scoring at least one Super Bonus in the mix triggers an enhanced version played on a fully-expanded 6x8 area, and the Both Ways feature always active. Any Nitro Reels scored during the bonus round remain sticky until its end.

X-iter Bonus Buy

ELK Studio's proprietary X-iter function offers instant access to several enhanced spins for fixed prices (some jurisdictions may have this option disabled):

• Bonus Hunt (2x bet) more than double the chance to trigger the bonus.
• Nitro Booster (10x bet) guarantees 2 features every time the Booster activates.
• Super Spin (25x bet) guarantees Max Rows and Both Ways enhancements for one spin.
• Bonus (100x bet) activates standard free spins.
• Super Bonus (500x bet) activates super free spins.

Nitropolis 4 On Mobile

The slot runs smoothly and dynamically on all mobile devices thanks to the newest HTML5 technology. Its structure, especially the increasing rows, fits perfectly into the vertical orientation, making the most of the design when the reels expand to 8 symbols high. The landscape version is modeled after the desktop format, with the exact element proportions and screen estate distribution.

Final Thoughts

We have nothing but respect and admiration for ELK Studios for creating a series of four games based on the same theme but continuously improving on the technical side and developing the backstory. Playing the second or the third part, we already thought: "Ok, that's as good as it gets", yet here we are on number four which we would probably rate the highest. We especially applaud the art direction that consistently sticks to the same overall style, making the experience familiar while introducing significant changes that push the narrative forward. And so, emblems of all four factions take an entirely new form representing each group's particular role in the new endeavor. The same goes for the characters equipped with unique tools indicating their designated tasks. We're confident that nobody would bat an eye if such details remained unchanged, but it's this type of commitment and involvement in the game creation that deserves applause.

From a technical standpoint, Nitropolis 4 borrows a lot from its direct predecessor, and even though the extras are not numerous, they make a massive difference in some situations. Take the Max Rows feature, for example. In base game circumstances, it might not be perceived as a huge help, although it undoubtedly provides an excellent opportunity for a sizeable win. In the bonus round, however, scoring it relatively early means full reel expansion until the end of the free spins, thanks to the safety levels mechanism. Nitro Booster activation also feels like a more achievable method of acquiring features compared to scoring them on the reels before. Hence, the fourth part of the saga is a creative continuation of an ingenious story peppered with several additional functionalities that successfully boost the familiar experience.