Thanks for trying out our game! We really appreciate it~
Just a little insight regarding the things that you mentioned:
We did just impulsively decide to use it so we're glad that you liked how we utilized the asset pack.
That was my friend/teammate's idea and I was also surprised when that was a thing. Not sure if it was intentional but I decided to keep it in as it kinda looks funny in a positive way.
The Spicy Water (Green Water) was also something another player mentioned so I updated the tutorial to specify "Clear Water" or something like that. I'm not sure whether I needed to inform the player about that since in the Tutorial level, there was a small part of green water near the explanation of enemies and such, and also to let the player test it out and learn from it if ever they skipped the Tutorial level.
As for the background, we did want to make use of the other available backgrounds in the asset pack to change things up a bit. I just encountered a problem where some of the background assets there weren't working properly with the parallaxing method that I know and since we only decided to make 5 levels, we just decided to use 1 set of background to lessen the work that we have to do. I'm not sure if there's a proper way to parallax a sprite image that isn't a full image (half transparent, half colored so unity is only parallaxing the colored part so the sprite isn't moving properly) that's why we decided to do it.