Essence Shock

Tagline: Protecting Earth from Dark Stones

From the introduction:

One day a spaceship explodes out of space in a ball of light. The spaceship crashes in a mountain ravine and carries with it an alien species called Shocktanians. There spaceship crashed into an inter-dimensional storage location and this caused the shocktans to crash land on Earth. The spaceship also drag forth many small spheres called Essence Stones. The Essence Stones can combined with living creatures or machines to form powerful fighting machines. Many of the Essence Stones, called Dark Essence Stones, decide to conquer Earth. These Dark Essence Stones also want to find the components of the crashed starship so they can go bring more Essence Stones to Earth.