If, after seeing last week's "nuclear sub", you guessed that May would bring a pollution-themed level, you were right! Polluted Waterway adds new obstacles like the spiky sea urchin and bursting pipe geysers (similar to the lava spouts in Hot Water)!
I also wanted to share a little about how I build up this background image. In a 2D game like this, layering sprites is extremely important. In Photoshop, I have to export the cave top, cave bottom, and ocean pieces separately. I also have to create an additional layer that's the cave texture across the whole image, which is used to display stalactites and stalagmites in the game. They have a special mask on them which blocks everything except that very background layer, so no matter where one spawn on the screen, the cave pattern blends seamlessly with the top or bottom pieces around it.
The levels with overlays sometimes have even more customization needed. In the Davy Jones' Locker level, I added bits of fog that just layered on top of everything; that was very easy to just set another sprite layer in my hierarchy. The effect in The Deep was much more difficult, because I needed to add an extra mask that the angler fish and sub's searchlight were able to cut through, then make sure the effect for the Glow-in-the-Dark sub was put on top of even that! Finally, this level is meant to seem murky pretty much everywhere except directly in front of you, so this time I added the effect layer to the camera itself, so it moves when you do!
Stay tuned for one more update before our next launch on May 1!