Oxygen 3 Slot by ELK Studios

Third Dive into Coral Creek

Oxygen 3 is the third chapter in ELK Studios' underwater cluster series, and the feature list has gotten dense. The 6x7 grid returns with avalanche mechanics and cluster wins (5+ connected symbols), but ELK swapped out the Jellyfish and Octopus from Oxygen 2 and brought in the Clam - a wild symbol that opens to trigger one of three different sub-features.

The core identity stays the same. Oxygen Bubbles form on positions where winning symbols are removed. Each subsequent win on that same position doubles the multiplier - x2, x4, x8, x16, all the way up. In the bonus game, these bubbles persist between drops. That escalation is what made the original Oxygen interesting, and it's still the backbone here.

The Clam and Its Three Tricks

The Clam is a wild that triggers a feature when it lands in a winning cluster. Three possible outcomes:

• Pearl - Picks one symbol type and makes all instances sticky. Other symbols drop out and new ones fill in. The cycle continues as long as more of that symbol or wilds keep landing. It's a collection mechanic with a satisfying crescendo when it connects.
• Squid - Moves around the grid, dropping a wild on each position it visits. Keeps going until it exits the grid. Simple, but on a 6x7 board even a short run can create multiple wild clusters.
• Starfish - Rotates, clears payout symbols along its chosen direction, activates feature symbols it crosses, and pumps up the position multiplier. Repeats until it turns into a wild. The Starfish is the most disruptive - it can chain-activate Clams and special wilds it encounters.

Six Wilds, and They All Do Something Different

Regular Wilds substitute as usual. The Clam opens into a feature. But there are also Exploding Wilds that detonate in a cone pattern (up/down or left/right), clearing symbols and forcing a refill. And Blaster Wilds that convert surrounding symbols in an X or Plus shape into matching symbols - hit something that's already been converted by another blast, and it turns into a wild instead.

These interact with each other. A Starfish clearing a path can activate an Exploding Wild, which triggers a Blaster Wild, which creates new wilds that form new clusters. On a good cascade, the chain reactions get ridiculous.

Bonus Drops and the Oxygen Meter

Three Bonus symbols trigger 10 bonus drops. The Oxygen Meter fills up with each winning combination during the round - when it's full, it empties and places or upgrades a cluster of multiplier bubbles on the grid. Since bubbles persist across all bonus drops, later drops inherit the multiplier map from earlier ones.

If one of the three Bonus symbols is a Super Bonus, you enter the Super Bonus instead. Same structure, but the Super Oxygen Meter upgrades larger clusters of multipliers when it triggers. Retriggers add +3 drops for 2 Bonus symbols or +5 for 3.

X-iter Buy Options

Five tiers beyond the standard spin. Bonus Hunt (2.5x) gives triple the chance at the bonus. Mega Hunt (5x) pushes that to six times. Clam Chowder (25x) guarantees 3 Clam symbols on the grid for one drop - a mid-price option that's specific to this game. Bonus Game (100x) and Super Bonus (250x) buy direct entry with 10 drops each.

The 25x Clam Chowder tier is the unusual one. It doesn't buy a bonus round - just one loaded drop with guaranteed Clam activations. At 25x the base bet, it's a gamble on whether those three Clams can chain enough wild interactions to justify the price.

Big Symbols and Grid Scale

Symbols can drop in 2x2, 3x3, or 4x4 sizes. A 4x4 symbol covers 16 grid positions and counts as 16 individual symbols for cluster evaluation. On a 6x7 grid (42 positions total), a single 4x4 high-pay symbol takes up over a third of the board. Combined with Blaster Wilds converting neighbors into matching symbols, large clusters form fast when the pieces align.

The 25,000x cap sits at the same level as both previous Oxygen entries. With a 33% hit frequency, the base game feeds reasonably regular small wins - it's the bonus mode where bubble persistence and wild chain reactions push toward the ceiling.