Oxygen 2

Oxygen 2: Slot Overview

Coming up for a breath of air is ELK Studios' slot Oxygen 2, a sequel to the 2023 underwater release Oxygen. Possibly designed in response to the success of Pragmatic Play's slot Sugar Rush, Oxygen was a fiesta of individual reel position multipliers that could stick in place and grow to epic proportions. Oxygen 2 retains that particular feature while fiddling around the edges to produce a revamped, bubbly, aquatic escapade.

Players return to the deep when taking on Oxygen 2. A see-through gaming grid floats in a dimly lit subterranean grotto of coral, pipes, and sand. At a guess, it looks like the place where a submarine sank and broke into parts, hopefully not before the crew members were able to safely escape. Oxygen 2 wasn't as attention-grabbing an ocean slot as Razor Returns, for example, but its reels crawl with colourful creatures that have integrated themselves with the trash humans have spewed into the sea. A crab with a spanner instead of a claw or a snail living in a tin can, for instance.

For the sequel, symbols once again drop into a 6-column, 7-row matrix, forming winning clusters when 5 or more identical pay symbols are horizontally or vertically adjacent to each other. Clicking the coins button is where a stake of 20 c to $/€100 may be picked before activating X-iter bonus modes, depending on player preferences. With a 94% RTP, no matter the approach, Oxygen 2 operates a highly volatile math model

Oxygen 2's pay symbols are green, orange, and pink floaty things and 4 higher paying character symbols. Clusters of 5 OAK in size pay 0.1 to 1 times the bet, increasing to 10 to 100 times the bet for clusters of 16+ OAK. Wilds substitute for any pay symbol. An all-wild win has the same value as the highest-paying symbol. Symbols of 2x2, 3x3, or 4x4 may land on any symbol drop. Big symbols may have multipliers.

Oxygen 2: Slot Features

The game starts with symbols dropping onto the reels, and after winning symbols have paid, they either explode, or if the symbol is a special wild, it is activated to explode later. Following this, the reels are filled by symbols dropping downwards, and the avalanche feature continues until no new win appears.

Oxygen Bubbles & Multiplier Strike

The first time a symbol explodes, an oxygen bubble is activated on its position. Each time a symbol explodes on an oxygen bubble position the multiplier value is doubled. An initially activated oxygen bubble counts as x1. Oxygen bubbles do not tumble downwards, and the highest possible single value is x2,048. Also, triggering randomly on any spin, the Multiplier Strike feature places a random number of multipliers on the grid.

Jellyfish & Octopus Features

One or more Jellyfish may randomly arrive holding multipliers. Each Jellyfish stops at a random number of grid positions, adding the carried multiplier. If there is already a multiplier where a Jellyfish stops, the existing multiplier is added to the Jellyfish multiplier and the Jellyfish multiplier is added to the existing multiplier. An Octopus may also randomly appear on the grid and sit behind 1 symbol position. The Octopus feature triggers if a win occurs on the specific symbol position, adding a random selection of the available multipliers outside of the winning cluster to the win, increasing the win multiplier.

Exploding Wild & The Blaster Wild

The Exploding Wild triggers an explode feature when it is part of a winning cluster. The explode feature removes all pay symbols within two cone-shaped areas facing to the left and right, as well as up and down from itself. It triggers when no more wins appear. Exploding Wilds and Blaster Wilds within the cone areas are activated. The Super Exploding Wild activates all unactivated oxygen bubbles behind the exploded symbols.

The Blaster Wild triggers when it is part of a winning cluster. The Blaster feature picks a random pay symbol or wild symbol, then explodes and replaces all pay symbols with the selected symbol in an 'X' or a 'plus' shaped pattern. Any Exploding Wilds or Blaster Wilds in the pattern are activated. Symbols affected by more than one Blaster Wild pattern turn into wilds.

Free Spins

Hitting 3 scatter symbols in the base game awards 10 free spins. All oxygen bubbles and their multipliers persist when entering free spins and between free spins. The Octopus is also persistent in the bonus game and moves to a random position at the start of each free spin. Hitting 4 scatter symbols in the base game awards the super bonus game. In the super bonus game, the Jellyfish feature triggers before every free spin. The bonus game and the super bonus game can be retriggered. Hitting 2 or 3 scatters awards +3 or +5 free spins, respectively. If 4 scatters land, the bonus is upgraded to the super bonus +7 free spins are granted.

X-iter

Bonus modes can be activated from the X-iter menu. Bonus Hunt is where every spin has more than 3 times the chance of triggering the bonus game, costing 3x the bet. At 10x per spin, one spin guarantees at least 3 special wilds land may be bought. Octo Strike costs 25x and guarantees an Octopus and at least 1 Multiplier Strike on a spin. Buying the bonus can be done for 100x the bet with an Octopus feature on each free spin, while the super bonus with at least 1 Jellyfish feature and 1 Octopus on each free spin costs 500x the bet.

Oxygen 2: Slot Verdict

First and foremost, Oxygen 2 is a well-made cluster pays slot. If, and no one's pointing fingers here, ELK Studios was inspired to make this slot (and the original) after sampling Sugar Rush, the team did a fine job of reproducing the key components while linking them to exciting side features. As before, the main mission is ramming the reels with oxygen bubbles, then winning over the top of them, doubling the relevant individual multiplier values - up to x2,048 each. It worked like a charm in Sugar Rush as well as Oxygen and is able to work like a charm in Oxygen 2, too.

It's not all bubbles, however. Oxygen 2 has a stack of complimentary mechanics going on, or potentially going on. Two major draw cards are the Jellyfish and the Octopus. They are able to morph the core multiplier oxygen bubble action in wild ways and can be instrumental in jacking multiplier values, which is the name of the game. When Jellyfish don't lead to gains, they could be a little frustrating, though. The time they take to float over the reels and do their thing is a little lengthy and might break the game's flow. Admittedly, Jellyfish do help build spin anticipation. In addition, if they work their multiplicative magic, and Oxygen 2 has a win cap of 25,000x to shoot for, then all is forgiven. Jellyfish aren't the swiftest creatures in the sea, after all, though they are graceful.

After taking a big gulp of air to see what's happening down there, Oxygen 2 didn't come across as a phenomenal improvement over the first Oxygen game, but it does steam away into new waters. While Oxygen 2 might feel like it's a paddle to the side rather than a mighty leap forward, it's an exciting cluster-paying slot with a host of enticing extras.