Beast Below Slot

Beast Below drops you into an underwater abyss on a 5x4 grid with 14 paylines. 96.29% RTP and high volatility at 4 out of 5. Max win is 10,000x. Dark water, bioluminescent creatures, and Siren symbols that expand upward when they land on a winning line. I played 300 spins at €0.50 and spent most of that time watching bubbles float across an empty grid while my balance ticked down spin by spin. The underwater atmosphere is gorgeous but it doesn't pay bills. First 100 spins returned maybe €8 on €50 wagered. Pretty grim start.

Sirens are wild symbols that expand to the top of the grid when they're part of a win. Each one carries a multiplier between 2x and 200x. If multiple sirens sit on the same winning line, their multipliers add together before being applied to the total win. So two sirens with 5x and 8x on the same payline would give you a 13x multiplier on that win. Sounds powerful in theory. In practice most of my siren triggers carried 2x or 3x multipliers that barely moved the payout above what a normal wild would've given. One siren landed with a 12x attached and connected on a full five-symbol payline. That paid €27 and was easily the best base game hit of my entire session.

The expanding animation is smooth and well done. Siren rises from her landing position upward through the cells above, filling each one with a wild as she passes through. Visually it's one of the better wild animations I've seen in a Hacksaw game. Each expansion feels like something meaningful is happening even when the multiplier turns out to be a disappointing 2x.

Sirens' Call and Down Below

Three scatters trigger the Sirens' Call bonus. During this round Pink Sirens appear on the reels. These are semi-persistent wilds that don't disappear after one spin like regular sirens do. Instead they nudge down one row per spin until they fall off the bottom of the grid completely. So a Pink Siren landing on row 1 gives you four spins of a wild presence in that column, shifting down one cell each time. It creates this nice cascading effect where wilds persist and overlap with new ones landing above them.

I triggered Sirens' Call naturally around spin 220. Got three Pink Sirens during the round and two of them overlapped on the same column for a couple of spins, stacking their multipliers together. When both were on the grid at the same time the combined multiplier hit 9x on one payline. Best single spin in the feature paid 45x. The whole round totalled 112x, which felt like a genuine rescue for a session that was drowning before it.

Four scatters trigger Down Below, which is the premium bonus. Diver symbols appear as expanding wild reels with three oxygen charges each. When a Diver lands it fills an entire reel with wilds and carries a multiplier up to 200x. Each time a Diver uses one of its charges it can move to an adjacent reel. Three charges means a single Diver can potentially take over three different reels across three spins. I didn't see four scatters naturally during my session and didn't buy the feature either. The buy cost was steep and after getting a solid natural trigger on Sirens' Call I wasn't hungry enough to gamble more.

Atmosphere and Sound

Best-looking underwater slot I've played. Full stop. The deep-sea colour palette works perfectly. Dark blues and greens dominate the background with occasional flashes of bioluminescent cyan when sirens trigger or wins connect. Particle effects drift across the screen constantly. Fish swim behind the reels without being distracting. Sound design uses low rumbles and distant whale-like sounds that create genuine ocean-floor atmosphere without becoming annoying or repetitive. I usually mute slots after 20 minutes because the loops drive me crazy. Left the sound on for this entire 300-spin session and didn't feel the need to turn it off once.

Ended down €18 after 300 spins. The natural Sirens' Call trigger at spin 220 saved the session from being much worse. Without that 112x hit I would've been down closer to €50 easily. Would I play it again? Yeah. The siren mechanic has real potential when multipliers stack properly, and the Down Below feature with its three-charge Divers could produce serious numbers if they land with high multipliers and successfully move across multiple reels. You just need the patience and bankroll to wait for it.