Granny Pills: Defend Cactuses

2075. After an alien invasion, Earth is almost devoid of life and oxygen. The cactus was the only plant that survived. The aliens must destroy or steal all the cacti to prevent life on Earth. A brave grandmother planted the cacti on the road (to get the light), apparently to protect them from monsters. She explains that monsters are afraid of human medicine and that there is a large supply of it, as well as a loaded gun for emergencies. Help her and her cactus bring life back to Earth and banish the monsters!