The Japanese call them kaijû eiga, we call them, for lack of a better definition, Japanese monster movies, the ones where outsized creatures do battle, and stomp underfoot the toylike trappings of humanity. At one time scorned and belittled, and considered merely the province of children and developmentally arrested males, now they are considered worthy of academic study. Here is one example: an exhibit of Japanese monster movie posters from around the world at the Donald Keene Center of Japanese Culture at Columbia University.
For more Japanese poster art, check out this collection of images from Toho studios, the people responsible for most of the giant creatures we saw hopping across matinee screens.