In 3033, humanity has a tremendous development. Humans begin looking for a new civilisation outside the earth. With that growth, we discover many other societies. Many different kinds live on other various planets. On a trip around the universe, one astronaut's spaceship got broken. He has no choice except to land on a strange asteroid.
On this planet, he finds out new species. They are monsters that have the power of different elements. They are Etermon. To go back to the Earth, the astronaut needs to use the space gate. It is ruled by the master of this planet. The explorer has no alternative. He has to catch and train the Etermon to fight against the master. Then, he can have a chance to go home.