Oxygen

Theme and Design

Underwater themes are always popular and ELK Studio’s interpretation is bright and brilliant. The background is a dark ocean, with bold corals framing the transparent grid and shipwreck in the background. The symbols are all weird looking deep sea fish in neon colours and its kind of reminiscent of the Reactoonz series of slots.

While it’s not groundbreaking, it is a bold interpretation of the underwater theme and one that’s sure to have plenty of fans.

RTP and Variance

The RTP of 94% is considerably below what you’d hope for (the accepted average for slots is 96%). And the medium-high volatility means there are likely to be big swings between dry spells and larger wins. So, if you’re on a tight bank balance then Oxygen might not be the wisest choice. However, jackpot hunters won’t find many cluster pays slots with better max wins.

Maximum Win

With a top payout of 25,000x your bet, this is a game that will appeal to those hunting for big wins. The RTP and volatility are a pill that has to be swallowed, but for a stab at that max win? We think it’s a fair trade off.

Symbols and Paytable

Oxygen is played on a 6x7 grid and has a cluster pays mechanic. This means that you don’t need to match symbols on paylines, but rather need to land at least 5 matching symbols in any combination, as long as they are next to each other either vertically or horizontally. 

There are 8 pay symbols, plus three different types of wilds and a scatter. The low paying symbols are buoys and pay from 0.1x your bet for 5 symbols, up to 10x the bet for clusters of 14+. The premium symbols are the underwater creatures which pay from 1x your bet for 5 symbols, up to 100x the bet for 14+  symbols.

Interestingly, symbols can also appear in different sizes. So, instead of filling a 1x1 tile on the grid, they can land in 2x2, 3x3 or 4x4 size. This doesn’t have an effect on the payout, they just act as the equivalent number of symbols.

Features and Gameplay

Oxygen is bursting with interesting features that really bring this game to life. For those who like unusual mechanics, and lots of them, this is a game not to be missed.`

Wilds

There are three different types of wild symbol in the game. When it comes to making wins, they can substitute for any regular pay symbol. You can also make wins exclusively using wilds and these payout at the same value as the highest paying symbol - i.e. 100x for 14 or more in a cluster!

One thing we know for sure from our test session is that these show up frequently, but often without triggering a win!

Regular Wilds

Regular Wilds just substitute for pay symbols to complete clusters. 

Exploding Wilds

The exploding wild only activates when it is part of a winning cluster. When it activates it explodes all symbols in an X shape surrounding it. This triggers all other features that are within the boundaries of the X shape.

X-Blaster Wild

The third and final type of wild is the X-Blaster wild. This triggers only when it’s part of a win too. It replaces all of one type of symbol within that same X-shape with a higher value pay symbol from the table. And if any features are within the X, these are also triggered. And finally, if a symbol is triggered by multiple X-Blasters it turns into a wild. 

Multipliers 

When you make the first win anywhere on the grid, then a bubble appears on that position, signifying a 1x multiplier. Then, if you make more wins on the same position, then the number in the bubble doubles. In fact, every time you make a win on this same position, the multiplier doubles, up to a maximum multiplier of 2,048x. The values are wiped between ‘normal’ spins, but remain in free spins mode, which is pretty handy. 

Multiplier Strike

At any point, a multiplier feature can strike, with three different options. The first is the Multiplier Strike. This puts a random selection of multipliers on the grid.

Multiplier Collect

This can only when a multiplier spot is part of a winning cluster. It collects all multiplier views adjacent to its position and adds them to its own. Multiplier Collects may be persistent which means they keep collecting with every subsequent cascade, so you can build some tasty values.

Multiplier Dealer

This feature - our favourite - multiplies all multiplier values with the value shown on them (at least x2). The multipliers it does this to are in a vertical or horizontal V shape. It activates only when part of a winning cluster. Multiplier Dealers can be persistent too, meaning they keep triggering with every subsequent cascade.

Free Spins Game

Finally, the bonus round. If you land 3 scatters then you enter the bonus game with 10 free spins. Here, multipliers are persistent so they stick between spins and between cascades. That gives you the chance to build some really nice multiplier potential.

And ... if you hit two or three scatters within the bonus game, then you get an extra three or five spins respectively.

Super Bonus Game

If you land three scatters and have a persistent multiplier feature then 10 super bonus spins are triggered. In the super bonus game all standard multipliers are persistent and at least one multiplier feature is persistent as well. The same rule applies for landing scatters.