in year 1999...

huge alien spaceship crashed on Earth, after people found out that
its not an object from Earth, world has changed. Peace has disappeared. Two
most powerful aliances on the palnet went into war with the aim to conquer the alien technology from the shipwreck for themselves.

The conflict has moved over the mayan islands, which had been untouched by the civilazation and its conficts fo far. Now suddenly the native mayans watch giant mechanical birds fight over their heads. That reminds them of an old legend...