Behind the Sewer: Toxic Waste with Reu Wilde

The 8×8 grid gives us the space to do something a little different with cluster pays. Toxic Waste uses oversized features like the 3×3 Chemical Spills and 2×2 Giant Mutant Symbols, so we needed a larger play area for those mechanics to land without overwhelming the board.

It also gives the multiplier grid more room to develop over multiple cascades. Rather than just increasing the number of potential wins, the extra space creates more opportunities for clusters to hit, clear, and revisit multiplier positions, allowing the feature to snowball naturally as the sequence continues.

The toxic-green palette was really a test of high-contrast gameplay and how that translates into high-contrast thumbnails and marketing. We wanted Toxic Waste to jump out in a crowded casino lobby, so the bright neon greens are deliberately pushed against much more muted grey backgrounds and reel elements.

The difficult part was making sure that visual punch didn’t come at the expense of readability, especially over longer sessions. There’s a fine line between something feeling striking and something becoming visually exhausting, but we think the balance of muted environments with concentrated neon highlights gives the game a strong identity without making the grid too difficult to read.

That’s a tough one, because the features in Toxic Waste were really designed to work as a system rather than as isolated mechanics. The mutated symbols on their own aren’t necessarily something completely new, and neither are the Chemical Spills or the respin mechanic. But when they start interacting with each other, they create an experience that feels much more unique than any one feature does by itself.

So rather than picking a single mechanic, my favourite part is probably the way everything works together and can compound across a sequence. If I had to choose one of the bonuses specifically, though, I’d probably go with the one that starts with the respin. It gives you that immediate sense that something bigger could start building.

Me, probably.

But in all seriousness, we didn’t build Toxic Waste around some imaginary “ideal player.” None of our games really work that way. I think if you focus too heavily on one fictional player profile, you risk ignoring a whole bunch of real players who might connect with the game for completely different reasons.

We just like taking things people already understand and twisting them into something that feels properly ours. Grid slots have been done to death, especially on the candy side of the algorithm, so we wanted to keep the brightness, familiarity and immediacy of that format, but make it higher contrast, grimier, grosser and a lot less sweet.

So a candy-grid player should still find plenty that feels familiar, high-volatility players have something to get stuck into, and anyone who grew up on gross-out 80s and 90s cartoons will probably recognise the tone immediately. That’s about as deep as our “ideal player” goes. It’s deliberately broad, even if the game itself looks pretty niche. Tetsu in his headband and samurai gear gives the slot a ton of charm and immediate retro energy.

I fell in love with Tetsu while I was designing him. I think he’s probably a bit like me with his resting bitch face, punctuated by sudden bursts of ridiculous energy.

I can’t say for sure whether he’ll be back, but we do have a full-size cut-out of him in the office, so he’s definitely become part of the furniture. We’ve also kicked around a few ideas for where he could go next, whether that’s something like a comic-book-inspired book game or taking another familiar mechanic and twisting it into something that suits him. Whatever it is, I’d want it to have the same philosophy as Toxic Waste — recognisable at first glance, but with something genuinely different going on underneath.

As for the lore, Tetsu crawled into a sewer pipe beneath a nuclear plant that had been pumping waste into his swamp. Over time, he mutated into the lovable little rascal he is today.

Maybe one day we’ll see him emerge from the sewer and make his way back to that swamp. The bigger question is what kind of mechanic that journey would lend itself to? We'll leave you to guess what we could be cooking up.