What a coincidence, I just did something similar this morning (or was it yesterday). I made the inertia of the boxes be 50% instead of 95%, which improved their behavior significantly. But I also overhauled the ReactToPushBack and related functions. I haven't uploaded the results yet, but I probably will soon, when I have something else worthwhile to show. I also implemented a "seed" state for the sprout sprite so that a plant can start out as a seed. Then I implemented a water droplet sprite that will cause the seed to sprout and deactivate the droplet.