From the website:
" In Endless Monsters Upon Japan! you direct an unstoppable stream of monsters from your home city towards either Tokyo or Hiroshima. One player seeks to reduce the major cities of northern Japan to rubble; the other is against southern Japan.
The monsters are very active, and cause little trouble if allowed to run from city to city. But if delayed at a city they stomp about in frustration and cause great damage. True to the ideals of collectible monster games, the monsters enjoy fighting each other and grow in size with each victory. Moreover, the theme of collectible monster games also led the mad scientists to create three colors of monsters, each of which has an advantage against another.
The game is easy to learn and quick to play. Two playing boards are included: a chart makes learning the game simpler, while a map of Japan is prettier to use. There are numerous strategies, some of which will be discovered quickly by an adult player and others of which are more subtle."