The ocean might be vast, but Oxygen by ELK Studios doesn’t waste time drifting in circles. From the first spin, this underwater adventure makes it clear it has more on its mind than coral reefs and sea anemones. Set somewhere deep beneath the waves, Oxygen throws players into a dense grid-based setup populated by multicoloured sea creatures, buoy-like devices, and a scatter of unusual mechanics.
This is a cluster pays game with a 6x7 grid, where wins form when five or more matching symbols connect horizontally or vertically. It runs on an avalanche mechanic, replacing winning clusters with new symbols for consecutive win potential. Betting starts at 0.20, with a host of multipliers, features, and two bonus modes. The game also includes oversized symbols and ELK’s trademark X-iter options for feature-triggering buys.
Oxygen joins a long line of grid-heavy ELK creations, with more than a few echoes of titles like Nitropolis and Phoenix Graveyard when it comes to mechanics and presentation. And as usual, the visual polish is all there — fluid animations, cinematic sound design, and a smooth interface.
Here’s how you can get started and play Oxygen for yourself:
If you aren't already registered, click on the green 'Sign Up' button in the top right corner and fill in the required fields. You can then verify your account and make a deposit if you want to play Oxygen with real funds.
The paytable is split between low-value tools and high-value marine life. Wins require five or more of the same symbol connected, but larger clusters are where the more significant payouts could come from. Check out the complete paytable below:
Symbol | Payout for 5 , 10, and 14+ of a kind |
Green Net Creature | 0.10x, 1.50x, 10x |
Orange Net Creature | 0.15x, 1.75x, 15x |
Purple Net Creature | 0.20x, 2x, 20x |
Green Monster Fish | 0.30x, 2.50x, 25x |
Yellow SeaHorse | 0.40x, 3x, 30x |
Purple Anglerfish | 0.50x, 4x, 50x |
Gold Octopus | 1x, 7.50x, 100x |
Wilds pay as the highest-value symbol when in a cluster by themselves. Symbols can also land as 2x2, 3x3, or 4x4 blocks.
Every winning cluster explodes, allowing new symbols to tumble in and potentially continue the chain.
These wilds detonate in an X-shape once they’re no longer part of a winning cluster. Any symbols in their blast zone are removed, and if other features are hit, those activate too.
When this wild is part of a win, it selects one regular symbol and blasts all identical ones in an X-shape into wilds. If it potentially hits another X-Blaster or Exploding Wild in the process, those chain-trigger as well.
Winning on a specific position drops a bubble with an x1 multiplier. Consecutive wins on that same position double it — up to a staggering x2,048. These reset between paid spins but persist during bonus rounds.
Three randomly triggered extras give the multipliers some added bite:
Landing three scatter symbols awards 10 free spins. Any multipliers on the grid carry over and continue to grow throughout the feature. Retriggers are possible by landing 2 or 3 more scatters for +3 or +5 spins.
Triggered by landing three scatters plus a persistent multiplier feature. This version offers the same sticky multipliers, but guarantees at least one persistent feature — either a Dealer or a Collector — active throughout the round.
For those who prefer jumping straight to the action, the X-iter menu offers the following modes:
If Oxygen's feature-stacked bonuses appeal, you might also want to check out Tropicool 2 or Nitropolis TV, both from ELK Studios. You’ll find all these slot titles at BetVictor.