Wonderful art and very smooth animations! The color choices match the gameplay very well, everything is very vibrant and visually distinct. I also really like the shadows, those add a lot to the overall look! The controls feel right, but having run as the default with shift to walk may feel better. It's fun to weave your way around the black slimes and take mental notes about future approaches! The intended play time feels a bit on the longer side, different levels with a variety of time limits could be a way offer some options, and I think that once you add sounds and music there will also be a stronger sense of pace to the action.
It's a great little game! I encourage you to revisit it for a small update after the jam to add a bit of polish, because everything feels incredibly close to being fully complete.