The roughnecks are back in action and ready to drill for Nitro! Nitropolis 4 is a 6-reel and 4096+ ways to win online slot from ELK Studios with a drilling theme. The game comes with Avalanche, Nitro Reels, Nitro Multipliers, Modifiers, Big Symbols, Bonus and Super Bonus Games, and X-iter Modes.
Nitropolis 4 Slot Symbols
Symbols on the reels include low-pay card royals – J, Q, K, A, medium-pay clan signs; Rogue Rats, Pug Thugs, Gritty Kitty, and Dirty Dawgs, high-pay gang leaders; rats, pugs, cats, and Dobermans. A sea mine is the Wild symbol and substitutes for all symbols except the Bonus and Super Bonus symbols.
Nitropolis 4 Base Game
Nitropolis 4 Features
Avalanche Feature & Increasing Paylines
All winning symbols explode, except for the Nitro Reels, allowing the remaining symbols to fall until they reach a resting position. After this, an additional row is added at the top and new symbols drop in to fill the empty spaces. The feature continues as long as new winning combinations appear. Nitro Reels and Nitro Multipliers that are part of a win are kept and respin during the symbol refill.
Each additional symbol drop adds a row of symbols, up to a maximum of 8 rows, increasing the paylines. Nitro Reels and the number of symbols inside the Nitro Reels will also increase.
Nitro Reel always covers 2 symbol positions and contains 4, 6, 8, 10, or 12 of the same types of 1×1 symbols. A big Nitro Reel covers 6 symbol positions, and includes 2, 3, 4, 5, or 6 identical 2×2 symbols. If a Super Bonus symbol lands on a Nitro Reel, it is always counted as a 1×1 symbol.
All paying symbols and a Wild symbol exist in 3 sizes; Normal 1×1, Super 2×2, and Mega 3×3. All big symbols are counted as consisting of the number of 1×1 symbol instances it covers. Empty places below the big symbols and big Nitro Reels are filled with 1×1 sized symbols of the same type as the big symbol.
A Nitro Multiplier is a blocker that can appear in a Nitro Reel. The Multiplier holds a value of x4, x6, x8, x10, or x12 and multiplies all wins in view. The Nitro Multiplier is only counted as one 1×1 symbol.
The Nitro Booster consists of 2 screens that may award features before the main reel stop. The Nitro Booster moves upwards and conjunction with a win when the reels are fully expanded. There are 8 features in total; 5 of the features affect the main reels, and 3 affect the Nitro Reels.
Main Reel Boosters
* Both Ways – Wins are paid both ways.
* Redrop – A Redrop feature is activated.
* Max Rows – Reels are expanded to up to a maximum of 8 rows.
* Nitro Appear – Randomly places a Nitro Reel or a big Nitro Reel to the reels during the ongoing spin.
* Garbage Collect – One symbol is randomly selected and removed from the reels. Nitro Reels containing the selected symbol will respin.
Nitro Reel Boosters
* Nitro Wild – Randomly selects an existing Nitro Reel in view and fills it with Wild symbols.
* Nitro Upgrade – Randomly selects the existing Nitro Reel in view and increases its ways value.
* Nitro Match – Randomly selects the existing Nitro Reel in view and matches it with another symbol in view to create a win.
Landing 3 or more Bonus symbols trigger the Bonus Game with Free Spins. If a Super Bonus symbol land in a Nitro Reel, the Super Bonus is triggered.
3 Bonus Symbols award 8 Free Spins.
4 Bonus Symbols award 12 Free Spins.
5 Bonus Symbols award 16 Free Spins.
6 Bonus Symbols award 20 Free Spins.
Free Spins always starts with the safety level set to 4 rows. Every winning spin advances the safety level one row up to 8 rows. During Free Spins, all Nitro Reels are locked and remain in play for the remaining Free Spins. Super Bonus is played with Max Rows, and Both Ways activated. Landing 3 or more Bonus symbols in Free Spins award additional spins.
Nitropolis 4 Free Spins
* Bonus Hunt | 2x the bet – More than double the chance to trigger the Bonus Game.
* Nitro Booster | 10x the bet – Nitro Booster always provides 2 features when activated.
* Super Spin | 25x the bet – One spin is played with Max Rows, and Both Ways.
* Bonus | 100x the bet – Triggers the Bonus Game.
* Super Bonus | 500x the bet – Triggers the Super Bonus Game with Max Rows, and Both Ways activated.