"In the far reaches of the Milky Way on the distant planet Zi, there exist metallic lifeforms that possess superior fighting skills.  These are the Zoids.  Warriors by nature, Zoids have been used as the ultimate weapon in an ongoing war between Imperial Forces, and the Republicans of Planet Zi."
Van Flyheight is a young boy living on Planet Zi.  One day, he stumbles upon a cocoon that gives birth to a small "organic Zoid" whom he names Zeke.  Zeke has the ability to fuse with another Zoid giving it great power.  Also "giving birth" from a cocoon-like object is Fiona, a girl whom Van befriends.  In a resurrected Shield Liger Zoid, they set out to discover the secrets of Fiona's past.

Review: This is so much similar to Gundam.  I mean a boy (Van) stumbles upon a giant robot (Shield Liger) and finds himself caught up in a war.  But despite this, Zoids is in a class all by itself.  The characters may be one dimensional but it's very interesting to see how their incredibly different personalities interact, like Fiona's naivete and Van's cockiness.