Varmints

This setting of this short film is in a place with lots of green. The main character is a creature which actually looks likes a rat. In the beginning, the main character and all the other creatures and plants are living peacefully but then one day, other creatures starts destroying the nature and builds towers and factories. However the creature saves a single piece of branch and saves it and looks after. Soon after, one day the city gets polluted and makes it hard for the creatures to live in the city. At the end the tree branch starts creating bubbles and it turns out to be a jellyfish. Everyone escapes and it saves the creatures.