Gloom-shroom is a plant that fires fumes in all directions but with short range that heavily damage all zombies nearby. It can be purchased from Crazy Dave's Twiddydinkies for $7500 and is an upgrade for the Fume-shroom. It is unlocked between playing Levels 4-4 and 4-5. It is useful in Last Stand and other swarming levels, like Bobsled Bonanza.