This segment of Zombies Ate My Neighbors introduces GIANT ANTS in a level that's just one big spiral. It's the least fun level! Also in this part is the new level theme of the haunted office, we're about 20 stages deep and LucasArts is still pulling out new level themes on us. Look at that variety.
Also WEREWOLVES. And SNAKEOIDS. In a parody of the movie Tremors Draco stares down the Snakeoids which are basically massive sand serpents that are weak to the bazooka item. We're getting into the territory of forced minibosses that drop skeleton keys so these big enemies are forced battles.